I don’t think my boyfriends brothers girlfriend likes me very much and I’m worried it’ll affect our relationship

Hey everyone! So I (F23) recently started dating this guy (m21) and things have been going really well so far. I like him a lot and he just seems like an overall good guy that cares about my wellbeing. I met his brother for the first time a few weeks ago, they are roommates, and his long distance gf was there too. I was nervous about meeting them, but we were all drinking and played card games and had a good time. As far as I could tell at least.

She seemed really nice but there was this feeling I couldn’t shake. I knew they all met online and were all friends for a while before her and his brother started dating. The was she interacts with my boyfriend just makes me a little uncomfortable, the way she giggles and talks to him just kinda rubs me the wrong way and I don’t know how else to explain it.

I straight up asked my bf later that night if there was ever feelings there before her and his brother got together, I also know they haven’t been dating for very long. He told me that they were all friends and she is with his brother. I took that was a no and dropped it.

However, he was streaming the other night and he always invites me to watch. When I was on there she specifically brought me up and said I was really drunk. Which I thought was a little odd because we were all drunk and I know I wasn’t obnoxious or anything. Then tonight when I was watching, I texted my bf and said goodnight and told him I said hi to everyone, and when he told them that, his brother said hi back and she stayed quiet, and then changed the subject.

Maybe I’m overthinking it or reading into things, but it’s genuinely a gut feeling she doesn’t like me very much. She’s going to be moving in with them too and I’m not really sure how to go about things if she doesn’t like me. I’m just gonna continue to focus on my relationship and try to put it in the back of my mind, but I know him and his brother are close and we’ll probably all spend time together. It’s just frustrating because I wish we could all just be friends, but I feel like there’s nothing I can do.