<human>: I have a friend who I met in graduate school. She is generous to a fault, kind, and a loyal friend. Probably, my friendship with her is the best thing that I got out of my time there.

But she has major problems with relationships. They seem to blow up around her. Not just with men--with colleagues, too. I don't understand it, fully. All I can figure out is that she has little ability to judge or read people, and she deals well with me because I'm straightforward and have similar values to her.

Her relationships with men are a disaster. In the time we've been friends, I've seen her through three abusive relationships (and I'm 99% sure they all were in fact verbally and emotionally abusive). 

The last one was a doozy, yet she can't let go of being "friends" with him. Now, she has a serious boyfriend, too--and I cannot tell whether he's another abuser, or her perception about other people's wants or needs is simply very off.

I really care about this friend, and I want to remain friends with her. But her lovelife stresses me out so much. I had an abusive relationship and escaped it, so there's some trauma there. She asks me for advice, but cannot seem to take it fully.

When she was with the last abuser, I put distance between us to survive. But I missed her.

Is there anything I can do to remain friends with this person I care about, yet still protect myself (eta: emotionally)? I don't think there's anything I can say to protect her.

Can you condense the text into three sentences or less?
<bot>: My friend repeatedly gets in abusive relationships, and it causes me a great deal of stress. I don't want to lose the friendship, but don't know how to protect myself (emotionally).