Roommates

I live with 3 other girls in South. Two of them I really like living with but the one i think is crazy. She has some how gotten it in her head that we are dirty and never clean. Yet I clean every weekend. Here is the kicker she keeps writing things on facebook, like how she needs new roommates. I have no clue what I have done to her. I never talk to her or see her because her door is always closed. The other day my roommate tried to talk to her and she wouldn't even speak back and when she was asked to turn down her music she just turned it up. Now her music is loud 24-7. In South we have our own bathroom and shower between the 4 of us. The crazy roommate has 9 bottles of shampoo and conditioner that live in the shower at all times. None of my stuff is ever in the shower, I have to keep my stuff in a bucket on the floor. All of her stuff takes over the counter tops in the main hallway, so there is no room for anyone else to put anything. Which we can't do anyway because she would just move it out of the way so she could put more of her stuff there. She has no friends and I can see why because no one is able to put up with this stuff. I just wish that she would move out since she didn't even choose to live with the rest us it shouldn't be that hard. I about to go to my RA a say something about what has been going on. If I knew what I had done to upset her I would be fine and do what I could to change it. Since I have no clue what that is, its just making me crazy that she is just sitting over in the next room wanting nothing to do with the rest of us that live here.