Need advice about a girl I’ve known for a while

I (M18) have known this girl (F19) since middle school. We started to become friends in high school, but she was closer to my brother than me. I’ve kinda liked her since the start of high school, but I never did anything because me, her, and my brother are all friends and if I asked her, it would probably make things weird. Every time we hang out, she’s really nice, but I can almost guarantee that she doesn’t like me. I’m a very quiet/awkward guy, and she likes to party a good amount. I’m just wondering if it’d ever be alright to tell her, or how I can kinda stop liking her if I shouldn’t do anything.