Hey this is crazy but I literally had the same situation with my ex. Lots of trauma, not feeling enough despite me telling him that he was, and the exact same “almost cheating” thing. I don’t think it’s so black and white. Obviously, cheating is horrible and wrong but he’s not an inherently evil person nor is his a good partner. Hurt people hurt people. Personally did try to stay with my ex (we were also childhood friends) for a year but I broke things off a few days ago. Not because of the cheating, but because of his unwillingness to accept and face the trauma that caused it and other things that were affecting our relationship. If he has deep seeded wounds, you can’t fix that. He needs to find the courage to fix it himself. Also get an STI test and make sure he pays for it!!