A friend might hurt herself

Honestly, I don't know. I think you should do some online research about the issue so you can better confront and help your friend. Also it would be worth researching safety plans so that when something bad happens, she has a plan in place to minimize the fallout. Have you tried asking her why she thinks she'll never be in a normal relationship? Abusive relationships definitely can leave emotional trauma on their victim so maybe recommending she see a professional, or just give her some hot-lines and websites where she can go when she needs to may help. Abusive relationships are serious and it's really good that you want to help her. I wish I could be more help but this is something I don't have much knowledge on. Good luck.

Well first let me explain the self esteem issue problem, When your so use to getting mistreated and abuse you tend to get use to it. When a person put you down so much you tend to get use to that also. So when a person gets "normal" they become scared because they don't know if they trust this person would they abuse them, so since they don't know they rather have something that they're familiar to. I think she has a problem with herself within and i think your a great friend for trying to help her, but if she feels like she need to be in an abusive relationship their is only so much you can do because she feels that is all she knows.I think your friend need some psychiatrist evaluation that can help her achieve her goal and make herself feel some kind of self worth so she won't have to endure anymore pain within.

I think the other two replies hit the nail on the head with their responses, but maybe you should try set her up with a good friend of yours, and if you're with someone, go on a double-date. Maybe getting her out of the routine of dating the abusive partners could have a positive affect on her, and she'll start recognizing signs of a negative relationships she subliminally missed before.