Sharing Our Innermost Thoughts

hi guys,
i feel so stuck at the moment. my mum is with a guy that constantly drinks and when he does he gets mean and passes out on the couch. my mum always defends him and says “he has a lot on his plate right now " or " he hasn’t been drinking as much” they fight all the time even when she denies it. his been a complete a**hole to me the whole time I’ve known him, he called me horrible names and said things like “you wonder why your dad doesn’t want you” i never got an apology instead i got yelled at for showing attitude back to him after he said those things and he never got in trouble. every time he drinks it takes a massive toll on me and i sometimes i need to just talk to someone about it rather than bottling it up . my mum told me "if you say anything to anyone i will be VERY mad " and "i wouldn’t tell anyone about your business " so i cant talk to no one about it and especially her as she always gets defensive and I’m always the bad guy in the end. Every time me and him get into a fight they always use things against me such as “his good enough when he can buy you things” .its such a toxic household and i feel so trapped.