It VERY possibly could be that you really can't do anything to make this situation any better, she's not sure what she wants. If she's going to tolerate her ex and listen to his "psyco" threats, then it doesn't matter how intelligent she is, she's EXPLOSIVE, and you'll always have to worry about her and/or her ex doing something WACKO. You have got to think about YOU. Emotionally, this girl is taring you apart and you're going to end up wanting to kill yourself. Let it go! Save yourself.