Do you have a little brother, or sister, mom? If this was what they described to you would you tell them to stay or leave? Breaking up is so hard. And sex with the wrong person can be amazing. But.. From what I read.. You don't seem happy. There are so so so so so many beautiful people in the world who would treat you with love, respect, & kindness all of the time, not just some of the time. People who would never dream of hitting or hurting you.

I really disagree with everyone suggesting therapy. I agree with snakecharmer. Leave & don't look back! Better things await you. Don't keep yourself in a ****** situation. She hits you once shame on her, she hits you twice shame on you ..