Would you stay or go?

My boyfriend and I have known one another for years and have dated off and on. I’ve of course met his family and his dad is amazing. He’s taken me on trips and I’ve been able to experience a lot of things because of him. I didn’t have a great home life and was living with my alcoholic dad until my boyfriend asked me to move in with him. I only pay for cable while he pays bills, for food, and anything else either of us could need. Sounds great right? Well here’s the catch, I posted about this earlier today but I received some screenshots on Facebook of him planning on hooking up with another girl. The FB account was clearly fake but it was my boyfriends email and pictures. He called the girl who did it and fought with her over the phone for hours. He was telling her that he chooses me and that he was going to fight for me. The next morning he was on his phone all day and kept asking me for gas money. I eventually gave in and allowed him to take my car. He left around noon and didn’t come back until after one the next morning. He told me, he went to see a friend and I believed him. On Thursday we went to my moms to celebrate my birthday. He stood in the kitchen playing on his phone and didn’t even take any pictures with me. I don’t have the money to get my own place so leaving would mean having to move back in with my dad as I’m in school and would have too long of a drive if I moved in with my mom. But with my boyfriend, I get to stay for free. Also btw my boyfriend has cheated before and I did leave that time and when I came back I thought things were good that we would get married but he told me that he doesn’t know what he wants. And from what I know about this other girl, they fight a lot but he always comes back to her, I just don’t get it. 😞