If you read "How to Improve Your Relationship Without Talking About It".....it says that the very very high high majority of men who leave their marriages leave with another person fully in place or they have their eye on them.
My H constantly wants to remind that he didn't leave for another person. That's BS and it's never going to be resolved. He believes what he believes because it makes him look better. I know that he left with his eye on this other person.
Oh and if it makes you feel any better, OW went out and got a boyfriend who she is now engaged to after five months and only seeing each other on the weekends....and she was messing with my husband the very high majority of the time.....feel for her fiance, but not my problem....so that keeps with the statistics that these things tend to not work out.
