Horrible relationship, cant get out,what can i do?

ive been dating this guy for almost 4 years,things were great, went bad, got worse until he started physically hurting me and treating me like this. We split and had a lot of time apart and finally reconsiled. he informed me that he wanted to read "men are from mars and women are from venus" because he wanted it to help our relationship and at this point our relationship was flawless, we hungout together and with friends, threw BBQ's with friends, had time apart, did everything a couple does togetherand not once argued. Then one night his best friend was turning 18, they were gunna drink. his best friend wanted to go to the strip club and my boyfriend is aware that im not comfortable with him going there when he isnt single and he compeltely agreed. I asked him how the pong was going and he said great and was super nice about it. The next day he comes home around 11 am and is being "weird" doesnt talk to me or anything. The days after that he stops hugging me kissing me and saying he loves me, he comes home from work changes and leaves without a goodbye. i dont text harass him or call him at all to give him space, he was sitting outside a moment ago with another one of his friends talking about girls on facebook he would **** and whos hot and stuff like that and he wasnt aware i was listening. His facebook had a girl that caused nothing but drama between us on it, she hurt us bad and he has promised me on multiple occasions they dont talk but obviously thats not true. Im 18 and i live with my "boyfriend" i have no job yet cuz im still finishing up some classes. my mom refuses to let me come live with them in maryland because me and my step dad got physical and she doesnt want the drama. My grandparents canot afford to get me to come live with them, i have no where to go, no money, i need to get out of this relationship pronto but idk how. please help me. im desperate