Hi,
Looking at it from a blokes point of view,it sounds like a guilty conscience and he wants to clear the air for the future, I know when I was going to get married,I had no doubt I loved the girl I was marrying and she was the one for me, BUT,the sudden realisation that my "pulling days" were over was a real shock to the system,so whenever I went out with mates I would chat to girls to see if I still "had it"
I never crossed the line,never even kissed them,your hubby did, the guilt thing is the only reason I can see, but then I am a bloke and we are a bit thick at times,really hope you can work through this, good luck and take care, Ray