Recently my relationship w my FH has taken a turn for the worse.... 

a little back story... we've been together for Four years and live together. His ss6 and I have a great relationship and always have. Although his BM causes drama and is annoying, she and FH were never together ("dated"for 2 weeks, more like a texting relationship and meet up to have sex and that's how the child was made) although she was pretty obsessed w FH due to him being the dad. 
 

however, lately things have gotten pretty rough, and idk if it's bc of the stress going on in the world or what... but FH has been incredibly cruel and hateful. He knows I have diagnosed depression and anxiety and he disregards it as a fluke. Doesn't believe it to be real even though I have a doctors diagnosis. I find myself hiding in the bedroom lately bc he is so hateful. I'm even self harming bc I cannot deal with this hatefulness. He doesn't even care about the self harm and he thinks it's embarrassing if I do. I'm worried I'll end up ending my own life at this point. 
 

you might wonder why not leave this relationship.. well four years of my life are already gone.... wasted my best years.... my twenties are just gone. How will I live with myself? Will I find someone else? I don't even think I'm lovable at this point. He tells me I'm a monster all the time. He has been calling me the absolute worst things.. knowing I have some serious mental issues, that he fully doesn't believe in. And that he will tell ppl are a joke. Idk how I would be able to go on after this relationship knowing everyone would know all that. I'd rather just keep on trucking and trying to be strong.... idk. I really have no one in my life. I have like 2 friends and my family is tired of hearing it so I stopped resorting to them a long time ago... please if anyone can help id really appreciate it I'm at the end here...