Rude Roommate?

So am a new student at a new school and feel there is tension now with my roommate I'm sharing my room with. I think it is because she has ADD, but she and her new friend seem rude lately. I try not to interfere in her life, but still things are strange. Went canoeing recently & since she likes outdoors, I invited her to come along. She mentioned that her friend is coming. No problem. However she & her friend completely ignored me. When I tried to join in I was out of the loop. This friend of hers is her other's good friend's roommate. They seemed nice when I first met them. But for some reason they seemed cold towards me after. She came back late last night & seemed moody. Knew she was pissed so said nothing to her except how her kayaking trip was, which to her was ok. She was mad and it couldn't have been at me since I hardly saw her all day. She was getting ready for bed & turned the lights off. I said "have a good night" to her & she flipped out at me saying how I do not understand the connection between lights off and ME being awake? She's was the one going to bed! I can't say goodnight? Today she invited me to get nails done with her other friend. Was ok but she kept inviting everyone to go to a party with her with me stuck in the middle hearing it. Flaunted it to my other roommate and stuff but didn't mention it to me. WTF?? I'm not offended and told her that she does not have to invite if she does not want to, she does not need to rub into my face! How to deal?