Bad family life... Help me please

I hate my stepdad. He is the most irrational, horrible, selfish person. He needs to put down other people to feel powerful. He is uneducated and unkind. He has told me I'm a bitch, I'm the worst person he knows and that I don't deserve anything in this world. Now that I'm 18, he wants to kick me out but I seriously can't support myself. He has actually said he's going to make living in this house so hard for me that I'll want to leave. He doesn't let me eat any food from the kitchen unless I ask him permission and he sometimes say no if he's not feeling like it. I'm not allowed dinners anymore. He never talks to me like a normal person, but more like he's my controller. He constantly puts me down and makes me feel unwanted and uncomdortable. I spend most nights crying and wondering what I did wrong this time. My mum is conflicted but often takes his side. I had being in this house-what the hell do I do?