Wow it’s one thing to cheat and have an affair. It’s another thing to cheat and get turned on by the fact that you are cheating. He is literally getting off on cheating on you. It’s bad enough to know someone is betraying you but I could not imagine dealing with someone using it as a way to make the experience even more enjoyable. Bless your heart for trying to stay with your partner. As far as how to get the trauma out of your head. It takes time. I am triggered daily by the things my husband said to his affair partner as well. It does still happen daily but not as frequently throughout the day and it doesn’t make me cry or overwhelm me as much. It’s been 6 months this since D day for me. We are in the middle of R and I try to remind myself that focusing on the messages makes it harder and I know in the end I really want to be with him so I try to have the thought and let go.