Blamed for everything?

Why does my family blame me for EVERYTHING even if I didn't do it. If my mom's boyfriend waste toilet paper he blames me.(He throws a whole roll down the toilet and cloggs it just so I'll get in trouble) If there's trash on the floor and it isn't even mine I get blamed for it, if her boyfriend gets up and starts yelling at me for absolutely no reason It's MY FAULT. Seems like I can never be good enough around here and I'll I do is try.. he also tells her all the time "I'm trying to split them up and that ain't going to happen" when I literally don't even do anything. Obviously I can't control who my mom dates so how the hell am i trying to split them up when i don't do shit?