This is happening in my family. I bet he has read your books. I bet that he feels as badly as you do. Write him a letter. Stop by his house. Make the first move. If he doesn't accept, it's on you. Quit blaming yourself, the choice was his. My sister has said unforgivable things to me. I forgave. Because she is my sister. I am angry with her now but I if she needs me, I will go. She is my sister. You need to do the same.