What to do with an emotionally abusive parent?

I don't know what to do anymore. There is not a day that goes by where I don't cry for hours anymore. All she does is yell at me, call me names, she makes me feel like she hates me. Like if I died, she would be a happier person. I'm really at my wits end with her, and it's not like I can afford to move out. I do have a job, and I'm going to be 19 soon, but I need to save up every penny from that job for my second year of university because money is really tight this year. My dad has cancer and is not working right now, and I want to help my parents out as much as I can with paying for it. But, it's not healthy to live here, and I don't know what to do, I really don't. My mom tells me things that no good parent would tell their child, that I'm a lost cause, that I'm ungrateful, she constantly yells at me, and always picks fights with my step dad too. She's out of control and thinks she;s always right. She's making my depression twenty times worse than it already is, and I already have so much to deal before her abusive. I stay cooped up in my room now, afraid of what she might do next, I am legitimately afraid that my mother will start hitting me. How do I deal with a very emotionally abusive parent?