I've been there, done that, and I stayed with the girl WAAAAAYYYY too long. Like, I-was-pulling-sharp-objects-out-of-her-hands too long. I was young and stupid as FUCK.
Get out of it. Give yourself a few weeks. Don't commit to a relationship with anyone else for that time, although maybe you'd want to fuck around. I don't know. Just DON'T stuck witha crazy bitch.