I know this is a wall of text, but I would love it if I could get some advice.

This situation goes back for almost a year. My boyfriend and I had started dating, and we usually were found hanging out with my best friend. In one of our conversations, she confessed what her perfect guy type was, and my boyfriend couldn't help but laugh. We found out why a few days later, when he presented his best friend, who at first glance sounded like a perfect match to what my best friend had described.

They went on dates to the movies and hung out for a long time, but her being extremely shy and uncomfortable with her body (she's overweight, with low self esteem) she never made a move, or let him so much as kiss her. After they dated for a month or two, she invited him to her mom's wedding, where he confided in me that he was interested in her, as in more than friends. As her best friend, I was excited and told him to go for it when he asked for my opinion.

Long story short, they ended up together, just never established their relationship... By this I mean that they dated, were usually found making out, came back home at 3am and acted mostly like a couple should, except he would never admit to being committed and would never ever call her his girlfriend.

He began being sweet, but then started to blow her off, criticize her looks, tell her how she should look so he would find her attractive, and basically became horrible. He then disappeared for weeks without letting anyone know where he left (or why), but through my boyfriend I learned that he was hiding from my best friend, because she was extremely clingy. (It's probably true, she called the man like 7 times in the span of 2 hours!)

In any case, they broke up, got back together, broke up again... and that time, we all thought they were finished for good. He was fooling around with other girls (actually sleeping with them, too) while he kept promising my best friend that he only wanted to be with her, when he was ready.

It was on Valentines day that he told her that he didn't want anything to do with her, that she was weird and creepy, and that she was (pardon my french) just a little fuck. He broke her heart, spat on it and then stepped on it on his way out. She cried the whole day, and we (my bf and me) went to her house to make sure she was okay. She and him didn't get along very well, because she kept saying that he was useless and that he was too much of a nobody to be with me. She hated helping him figure out my taste in gifts so he could surprise me, and helping him overall, because he acted so differently than her ex (jealousy, I guess?). We ended up leaving her when she felt better, but ever since then, she's been... strange.

She has been in a mental hospital several times for attempts of suicide and severe depression. Her whole family got worried sick for her, and tried their best to make her feel happy. As friends, we stayed with her, even when she had her mood swings and acted hateful toward us.

This kept on for months, and after her episodes came more often, we saw that she had started doing it to call out for attention. Her friends (myself included) started to slowly back away, because no matter what we did, when she got depressed, everyone was to blame, even if we were trying to cheer her up. She also began to make up stories about my boyfriend because she wanted for us to break up so I could spend more time with her, because we weren't "as close as we were when we were in High School because of him".

In this whole mess, her brothers got extremely mad at my boyfriend's best friend for hurting her so deeply and threatened him. I know her brothers, and thought they would never really do anything about it. She told me about it after they both had cooled off, so I thought she meant it as a joke. She also confessed that they were going to beat my boyfriend, but wouldn't tell me why. I hate to think this, but maybe its because her relationships failed and ours is still intact? She always seems to be against him and criticize everything he does and believes in. The thing is, when she told me that they wanted to beat my boyfriend, I thought she was kidding. I was mad at him at the time, and jokingly said that they should teach him a lesson. We laughed it off and kept on as if nothing had happened.

Its been over four months since that happened, and a few hours ago, I received a text from my boyfriend saying "Ed is literally going to die now. Because of Dani." (Ed is his best friend, Dani is mine) After asking him for details, he said that her brother walked up to Ed with a knife and threatened him. I asked if Ed was okay, what was happening, but he hasn't answered yet.

I am super freaked out now, I don't know what to do. I'm afraid for both of them... I mean, I know Ed was a jerk and all, but I'm scared her brothers will do something terrible. They have changed lately, and now I feel that they are capable of doing something they might regret...

I have no idea what to do. I am terrified, and I don't know if I should be mad at her, her brothers, Ed, or myself for not telling my boyfriend about this.

Any words of advice are incredibly welcomed.

Edit:
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My boyfriend just texted me and said that everything is okay, but didn't give me any details. I am relieved about it, but he mentioned that her brother didn't do anything because he and Ed were with other friends. I'm afraid that something might happen if they see each other, and he's alone. Personally, I dislike Ed, but I obviously wouldn't want anything bad to happen to him. I'm also scared about the beating they had promised towards my boyfriend (which he knows nothing about).

Now that I know that he's safe, should I let him know about it? Or should I try to brush it off, because honestly, the one in danger is Ed. I'm so confused, I feel trapped, because even though all of this happened, Dani has been my best friend for years, and her behavior is really hurting me as well. She knows this, and she just... I don't know. Once she told me that as long as my boyfriend made me happy, she was happy for me, even if she hated him. After this, she tried putting my other friends against him (and actually succeeded, somewhat). They don't even know him as well as I do and already they agree with her when she says that he's just a waste of space.

Trust me, she's had her moments. Once, when I was mad at my boyfriend (around the time she told me about the threats) we were bordering on breaking up and she helped me get distracted and managed to cheer me up. Then again, come to think of it, we almost broke up because of rumors SHE kinda started.

Urgh... I don't know what to do. I am so lost right now...

Considering the threat of violence is very real, contact the proper authorities. This is not your fault in anyway.

Once you've done that, and if everyone calms down enough, you should talk to your friend. Tell her your feelings, and what she is doing to upset you. Don't say "YOU are doing this and YOU are to blame." Rephrase it. Say something like "When you do thisthing, it upsets me in thisway. I want us to be friends, but what is happening now isn't going to keep our friendship."

If she continues to act that way, she is not your friend.

First post edited with more details, that in Italic is no longer important.
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The thing is, Ed doesn't answer, and neither does my boyfriend. It had been over an hour since the last text (mine, asking if they were okay), so I sent another one a few minutes ago, and still have no reply. I know what she's doing is terrible, but right now I'm more worried about what her brother might do than about our friendship.

I doubt they'd go as far as to seriously kill him, but the texts my boyfriend sent me just make me shiver. He sounds really freaked out too, and that makes me worry. I wish I knew what was going on!

They won't answer, and I don't know if I should ask Dani about it. I might flip and make things worse. I'm going nuts right now!

I have told her about what I feel towards her attitude, but she manages to change the conversation into her being alone and abandoned by all her loved ones, how she hates her life and wishes she could just die. Lately I feel that we've grown apart, and I'm actually thankful for it, but this situation just makes it scary.

I can't help but feel horrified about what could be going on. To top it off, I don't know where its happening, because my boyfriend only said they were at a park that they liked to go to.

Detach yourself from the situation. The girl has lost her mind because of her pain. Yeah, the guy was a dick but there's no need to make those kinds of threats. If the relationship is over and done with then her brothers need to stay the fuck out of it and she needs to stop trying to make you and your boyfriend miserable just because she wants you to wait on her hand and foot.

I agree with Vix.
Get away from Dani, its sad to lose a friend but sometimes its got to be done. Maybe in a few years she will calm down.
For her brothers, try to avoid them, if they persist then stay in groups and see what you can do about talking to their parents. It is seriously not okay to threaten someone.

i hope you turn out to be okay sweetie.

She was in an abusive relationship, broke up and started acting psycho, targeting your boyfriend. Yeah. You need to phone the cops. Threatening violence against your boyfriend for something he had no control over is ridiculous. His friend was a scumbag. And I'm sure he felt bad about setting her up with a jerk. But when he's getting threatened, it's time to get the police involved.
If her brothers actually hurt someone because your friend couldn't cope, they will go to jail and ruin their lives over NOTHING. This is something that needs to be stopped before it goes any furthur.

Keep your distance for a while and give her some space. She should tell her brothers to quit acting the way they are now, but seeing the fact that she isn't doing anything to stop it isn't really what a friend should do, in my opinion. I know you've know Dani for YEARS now, but if she is about to go psycho over a guy that was a total dick probably to begin with? Give her some space and encourage her to think about her decisions. She shouldn't be making you and your bf miserable because you guys are together. Its her problem, not yours.

I wanted to talk to her about it, but noticed that I had 3 missed calls on my cellphone, 2 texts and around 5 missed calls on my house phone. (Most were on the days my boyfriend is allowed to visit, on his specific hours. Which she knows about, because I've made it clear that I won't talk on the phone unless its an emergency during that time.) I got mad, so I didn't answer.

I thought about distancing myself from her from then on, but another friend needed help and I ended up giving her a ride to Dani's house. I dropped her off, but didn't even say "hi" to Dani... I feel like a bad friend... but then I think that she knows that she's getting on my nerves, causing trouble with everyone she knows because of her personal issues and basically making everyone's life a hell.

I just wish we could go back to the time when we were friends and all this drama was behind us, but in order to do so, I'd have to accept her obsessive behavior and practically give in to her every whim. I don't want that, I just want her friendship, without so much... urgh... problems.

She needs to visit someone professional because it appears that her mindset is twisted and she's taking things too far. Killing someone because of that? There's not a single good reason to take someone's life (Of course if that person is about to kill a lot of people, then it's necessary or self-defence, yada yada). She seems to be consumed with herself and her feelings. She needs to get her head out of her ass and take a look at the situation she created. I hope things go well and I really hope she gets the help she needs. :( This is horrible either way.

I can sort of relate to the first part because one of my best friend's acted the same with the clingyness and she couldn't speak about anything else than her & her ex for ages. She even attempted suicide. It's frustrating when people are like this and you can't reach into them no matter how hard you try.

Maybe she needs a wake-up call? I'unno.

I say set her straight and talk to your friends. Your friend is destroying your life because of her spinelessness. She's crazy.

First thing you need to do is take a good long time to sit and do nothing but think about the situation. Somewhere away from people. Think about what is really most important to you.....the safety of your boyfriend or your friendship. It sounds like its come to the point where its gonna be hard to keep both ends in tack without tearing yourself up. Choose your battle.

If you do come to the decision that your boyfriend is more important, then talk to him about the situation. Bring him into the battle for support.

Actually something really similar happened to my bestfriend. Really, there's nothing you can do. I was there for my bestfriend up until she started being extremely rude to me and my now ex (but we're still friends, nothing happened because of her!)

The best advice I could give you is to probably get away from the situation--at least for a bit. Your friend really needs to figure out things herself. That's at least what mine did. Now I see mine every other day and she's in a relationship with a good man, it just took... a long time for her to figure herself out.

I don't know. Every person is different. Just let her know you'll always care about her.

Personally, I would've dropped Dani as a friend after I got her some help cuz she sounds like a crazy bitch. I'd remember the good times, but some people are just not good for you. Think about it. If you would've never butt in after that dude acted a fool with her, you woud have no threats, and you could live your life. Haven't you seen horror movies? The crazy bitch who lost love is always the one who kills all her friends or locks them away so they can never leave her. Or steals their identities.