If you or someone you know has experienced some sort of childhood trauma, you may understand that sometimes people repress these memories because revisiting them would be to revisit the pain that's associated with them. Your boyfriend is no different.
George M. says, "One secret would be one that's deep rooted in why some of us are the way we are. It could be from being molested at a young age, sexually assaulted, and anything in that realm . . . something even our parents, best friends, or homies don't know about. We wouldn't tell anyone this because of how we would feel misunderstood or looked at differently when people know about it."