I'm tired of holding myself back so I don't outshine you.

You know, some people never change. There are people I've been friends with for a long time, one girl in particular. And her boyfriend or ex boyfriend whatever abused her three times in the last month. And it's always while he's drunk. The first time, I gave him the benefit of the doubt because he is genuinely a good guy and I found it hard to believe he would do that. Then it happened again, but he started to take it seriously that he needed to get some professional help and that it was going to take longer than he'd like to deal with this etc. and she really believed him so I gave him another chance. THEN it happened again. And I refuse to support her being friends with him and being one of the main people to help him through it. I refuse to just sit back and watch her go through this. I told her it's a serious thing and by just immediately being there for him she's just showing him that it's okay to treat her like that.
I've been assaulted and I don't understand how you can allow someone to just be in your life like that again. I haven't spoken to him since it happened. I wanted to at first, to understand and now I don't have closure and I'm never going to and I've accepted that. What isn't okay is to use that against me. And that's what she did. And I get that she's scared and that she's hurting but it's not okay to make me feel like a bad person for being on her side and looking out for her instead of what her other friends are doing and supporting her being the main person to help him get through this.
I know it's her defense mechanism to make me feel bad and put me down and isolate her situation because she loves him and she wants to believe he won't do it again blah blah blah. I suppose I'll be what I always am and allow her to put me down to make herself feel better. I don't have much use for people like that in my life but I know that I'm the only one she has to actually be of some stable support.
What I don't understand most is that none of her friends have done anything. Like they have known this is going on etc. and none of them have done anything. If anyone ever hit me or any girl  for that matter my friends would kill the fucker. I had to beg my friends to not kill sofaking after my assault because I didn't 100 percent know it was him. If DK or PD or AD or JW or any of those boys were around when something like that happened, they'd kill the fucker. How do you just stand by and watch that happen?