What to do about my mom and her boyfriend?

Through out my whole 17 years, my mom had people move in with us. Cousins, friends, boyfriends. She would always let them occupy my room, get drunk (theyre older than me), make a mess, not pay the rent, have her ignore me most of time, be mean to her, and because of them, I would get locked out of the house and without a room so I would sleep in the couch of the living room. Now my got a new boyfriend this year, his name is Salvador. Theyve been dating for 6 momths and he decided to move in with us. This moron would try to act like he's my sister's real dad, a know it all, he thinks he's been through it all, arrogant, complaining the whole time, boss me around, thinks he knows better than my dad or any other adult and hes ONLY 25! and my mom is 35. Plus, he says hes been to college for 6 months and tries to be all knowledgeable he dropped out. I hate these kinds of people. I developed a complex; whenever my mom has people move in, I get very pissed and I never had a room of my own.