I dont really have any special insights other than compulsive behaviors are often a way of easing stress. They may not bring him JOY, but they may help him to make it through moment to moment.
This is nothing toward you at all, but if I were in his shoes I would rather be going through this alone rather than with someone else. Someone who had been repeatedly victimized as a child probably has trust issues, and to just be open with people about things where he was previously silent has probably been extremely difficult for him.