In cases like yours I totally agree with cutting them off totally.
I'd never let my family do stuff like they did and still want them a part of my life.
I did the same with friends that weren't really friends to me, they were only there as a reminder of who I was.
Wouldn't even you agree that I've changed for the better? I know I agree that you have, you are much different than the young girl I met 4 years ago.