What should i do about my girlfriend?

Me and my girlfriend have been together since i was 17 and she was 16, both of us were each others first love. She is so innocent and sweet, and i never have to worry about her cheating or anything because thats just not her. I love her more then anything, but when she gets mad shes really abusive. We got into a fight and i said i wish her family would die (because they are always taking her away from me. they just come over and pick her up and she doesnt have the back bone to say she doesnt want to go). When i said that she through a cordless phone and hit me in the face hard. so i broke her SIMS game. then she broke my Samsung LCD tv remote control. So i told her we were done and i wanted her out. so she left walking and she always thinks shes right, and im always the one chasing after her because i love her and dont want her to go. Its never her that comes back its always me. I want this to stop but i dont want to lose her, i love her so much. she was my first love and we have so many memories together, what should i do? please help.