The book thing has been difficult for him because as you mentioned it is very triggering.
The book thing was very hard on me. I must have read more than a dozen books. I would read until I was crying and then I would put it aside until I had enough strength to continue. One particular book I remenber. After a few days I got back to it. I was feeling good and I wanted to continue. So taking it from where I left off. The next sentence went something like this. "If a parent(s) told you that thier child bad been sexually abused, what would you tell them."
That just killed me. I was sobbing for over an hour. I thought I would get a lot further than one sentence. It took a few days to get up the nerve to continue. (That was a very difficult period I was going through.)