((((Sam)))) I'm sorry that you discovered that about him.
Let him go for now, Sam. At the very least, focus on yourself. When I snooped on my XW in July and found out stuff I really didn't want to know, it had the unanticipated benefit of helping me to detach, to let go, as I realized only then how very far she had to travel or grow in order to be a suitable partner for me.
Is some of that happening for you regarding your Ex?
BTW, only 2 wks til moveout/movein day, right? S/t to look forward to!