Good question and not an easy one to answer. I've had an assignment to write a letter to my dad. It was hard, but once I got into it I emotional attached to the letter. Part of the Prolonged Exposure therapy I did I was then suppose to read that letter daily. Eventually the letter wasn't that hard to read. The letter is not for your brother, it's for you. As a tool to help you work through this. Nothing about this process is easy. Sometimes it gets worse before it gets better. Just know that and don't give up on feeling better.