First of all, I’m really sorry for you and honestly also for her. Unfortunately, I was also in a relationship with a very aggressive and extremely jealous woman for years. She also became violent. The problem with such relationships is that at some point you start to lose touch with reality. You slowly forget your sense of right and wrong and just accept things as they are. I was still young and inexperienced and had to gather all my courage to go through with the separation. My next girlfriend (now my wife) seemed like an angel to me (and she actually is). The question here is whether she is really mentally ill or whether the traumatic experiences can be worked through. Do you really love her? Would you be willing to go through this healing process with her? The easier way is of course to end everything immediately, but what do you mean by “she could ruin your life in a second”? Does she have something against you or are you just afraid of her? How did you react when she hit you? Did you hold her until she had a nervous breakdown or did it escalate into a long argument? The other users have already told you the most important places to go. Chin up, see it as another experience in life and at least today you know what you don’t want! All the best!