Your brother is not ready to be receptive the way you would like. Right now he has too many anchors weighing him down and he is looking for a presence to dump some of them on. He may be in therapy but he isn't at a stage in therapy where he has gained any actual skills yet.
He isn't at a place where he is capable of seeing YOUR pain or challenges either. He has too many weights he is carrying of his own that he has no idea how to let go of. It's very much like trying to rescue a drowning person and when you get near them all they can do is pull you down instead of allowing you to save them.