I would like some advice because I have no idea what to do about the situation.
My roommate (S) is also my cousin. Her and her twin sister (N) and I have been living together for about a year, and it's pretty good for the most part. Two months ago though, she got a boyfriend (T) who completely and totally sucks. Every time he comes over, he brings out the worst in me; I am judgmental about things I normally wouldn't give a shit about when he's around. (he's got a kid, he never graduated high school, works at a dollar store, he does drugs [normally I don't think I'd care but S uses it as an excuse for his assholery, and I didn't think X turned you into a lunatic, I thought it made you love everything])
He's a raging asshole. I'd understand maybe if it was to me or to my cousin who's not dating him, since he knows us and knows we don't like him, but for an example I'll tell you something he did to this own forum's Liz. We were at Women (the band) and afterward, Liz got their set list. T's friend M asks her if he can have it, she politely says no, sorry. T comes over and demands that Liz give his friend the set list because "he deserves it", Liz is like "um, sorry?" T says again "No really, you should give that set list to my friend because he deserves it more than you. He listens to them a LOT" Liz says, again, "No, sorry." and puts it in her back pocket. T grabs the list out of her pocket. Liz says "No really, please give that back." "Why, my friend DESERVES IT", replies T. Eventually he does give it back, after first crumpling it up. Okay, I know it's just a piece of paper but he didn't know her; he'd never met her before. He went and acted like a raging asshole for no reason to someone he's never met.
He has done many MANY other similar things. I'd love to just ignore them and hope they break up as soon as they can, but not only does she bring him over to the house constantly, but I'm pretty good friends with his band mate and in fact that's how he and S met, so I see T out at the bars sometimes. Friday night I found myself screaming at him about "I fucking know you're a douche bag, T, you don't have to keep proving it. I FUCKING GET IT"
S's parents know that N and I hate T. HATE HIM. They also know how S has lied to them in the past (a very major lie), but somehow S has convinced them (apparently) that N and I are jealous and that we both have a crush on T, when in fact we just hate him because he is a terrible terrible person. That's the part that makes me the most mad; is that she is straight lying to her parents about me specifically. It doesn't matter that I was with a dude I'd been with for a year and a half at the time I met her stupid boyfriend and beside the fact that I think he's totally unattractive (before I met him).
They have only been together two months and he has asked her to marry him. Luckily she said not yet. It has been two months and I feel like I am going crazy because of her stupid junior high style relationship (he is her first boyfriend).