AITA for being a little bit annoyed my brother still won't forgive me for being a bit of a bully as a child?

YTA. Nowhere in your post did you mention apologizing to him for the bullying nor do you come across as even being sorry. You don't get to decide how he feels about your bullying or what his time frame is for moving past it. Constantly hearing negative things about yourself for years has a way of warping the way you think about yourself band you start to believe those negative things are true. It can take a long time to retrain yourself to stop believing those negative things. I'm 36 and I still deal with issues stemming from things that were said to me by my bully brother growing up and I don't think I can ever have a close relationship with my brother because of it.

/r/AmItheAsshole Thread