Today, my girlfriend and I got into an argument, which spiraled into me trying to break up with her, and then her refusing to let me out of the car and hitting me in the face and then me still trying to break up with her and her doing everything she can to stop me until I finally relented. What do I do?!?
At least in my book, violence is an absolute, zero tolerance dealbreaker. If it were me, then absolutely, positively, without question I would break up. I'd suggest doing it by phone or text, and making it clear that if she touches you or harms any of your property in any way that you will call the police. I'm sorry it's degenerated into that, but it's clear she has a problem with impulse control and terrible boundaries. The first and foremost thing is to keep yourself safe I think (hope) that once she receives notice from you, via whatever means, and has time to think, she'll come to her senses and deal with it. If you want to be ultra-safe, you might tell her via text or phone while staying with a friend for the night. From what you're describing, it sounds like she's really out of control.
I feel awful because I should have just left. I feel stupid. She apologized for it later, but that doesn't change the fact that it happens. For now, I'm going to distance myself a little bit while I try and figure out the best course of action, but if it happens again, or if it becomes threatening in any way, I will leave and notify the police while I'm at it. I just feel dumb because I let her think that everything is okay now :-/