I'll try to keep this short. So basically I(19F) am a first year college student and live in the dorms with two roommates(both 19F). Our families all live nearby, so all three of us go home pretty often. My one roommate, Allie, goes home VERY often so a lot of the times it's just me and the other roommate Victoria. Anyway, this week is finals week during college and all of Allie's finals are online so she just went home for the weekend and isn't coming back this week. I came back a few days into the week, while Victoria came back on Sunday. The important part is that Victoria has been alone in our dorm room for a few days now. The second important thing is that our dorm room is just one room with three beds, three closets, and three desks. Admittedly that's very little privacy.
Anyways, Victoria had texted me and asked when I was going to be back in the dorms, and I told her Wednesday afternoon. However, unfortunately on Tuesday night at around 11 pm I had a pretty big fight with my family and decided to come back early right at that very second. I took the train back and ended up arriving at around 2 am(Wednesday morning). I was trying to be quiet and enter so I didn't wake Victoria up but to my absolute shock I walked in on her touching herself openly.
It was super awkward as I apologized and looked away while she got herself decent really quickly. She was all red-faced but didn't apologize, and just said a quick goodnight and went to sleep. I got into bed too but thought about it and decided she was an asshole for doing that.
Like, the three of us share this one room. I woke up her and told her that (I don't think she was really asleep though). I just said I wanted an apology but to my absolute shock she said she was sorry I saw that but wasn't sorry for touching herself because it's her room too and that she hadn't expected me back at 2 am of all times and that I should have at least texted. I guess that last part is true but hindsight is 20/20 and also I was really shaken up after the fight with my parents and wasn't thinking too straight. I mean I guess she's always been less conservative than me and Allie but I never thought she would go this far. I was too shocked to say anything else so I just got back into bed. AITA ??????
Edit: A lot of people think that I was mad at her for masturbating. I wasn't. Our dorm room is literally just one small room, so it's a super close-knit shared space. I don't want her touching herself in that super tight shared space. I don't care if she does it off in the bathroom or something.