Thank for having such bravery to begin talking about this. I am certain it must have been difficult. It is too hard to know all the forces that might have played a role in your actions back then, but one thing I am certain of is that being able to reflect on your own behavior and transgressions is a good thing. It sounds like this may have caused a reaction between you and your brother that is now the primary issue. Yes? So perhaps the thing to do is to acknowledge there is an issue with him and begin talking to a counselor about the feelings you are having. If that seems too difficult you may just want to talk to your brother about making the relationship better in the here and now. If he agrees and you want help with that, perhaps you could see a counselor for a few sessions to see if you can improve communication. The issue may or may not be something your brother will bring into the session.
Finally let me say this: The way you have described your behavior does not mean you were psychotic or will be. It is very understandable that you would feel uncomfortable about your behavior back then, but it doesn’t mean you and your brother can’t have a good relationship. If I were you I would find out if you brother is willing to have a better relationship with you and take it from there.