Opening Credits:
Crazy Angel ~ Kill Hannah.
[Hopefully not because I'm going to end up batshit crazy by the end of it.]

Waking Up:
Boom! ~ System of a Down.
[Riiiiight.]

Falling in Love:
I Do ~ Placebo.
[Well that's alright, then.]

Fight Scene:
Stillborn Universe ~ The Kovenant.
[Now this could either be the lamest fight in movie history, or... no, no, that's all it could be.]

Breaking Up:
Guilty Pleasure ~ Cobra Starship.
[Bit of an upbeat breakup.]

Getting Back Together:
Again, Again and Again ~ Blaqk Audio.
[Yeah, getting back together really fucking fast. Seriously, this could work for real.]

Secret Love:
Starts With One ~ Shiny Toy Guns.
[Go on, then. That'll do.]

Life's Okay:
Dying In Your Arms ~ Trivium.
[That's seriously not okay, guys.]

Mental Breakdown:
They Can't Save Us Now ~ Kill Hannah.
[Us? I suppose schizophrenia counts as mental breakdown, right?]

Driving:
President ~ IAMX.
[Only if I was driving really slowly.]

Flashback:
Nine in the Afternoon ~ Panic at the Disco.
[Back to the street where we began. Sounds like flashback material to me!]

Partying:
Party Hard ~ Andrew WK.
[Ahahaha! Obviously makes up for the fact that none of my other answers have made sense.]

Happy Dance:
Son of Lies ~ Aiden.
[Uh.]

Regretting:
Prevent This Tragedy ~ Alkaline Trio.
[If you ignore the lyrics and only pay attention to the title, maybe.]

Long Night Alone:
Roses For The Dead ~ Funeral For A Friend.
[Oh, go on then.]

Death Scene:
Sick Boy ~ Kill Hannah.
[Hello, overdose.]

Ending Credits:
Adieu ~ Enter Shikari.
[Aww, how nice.]