Don't bring it up! Believe me, nothing good will come from it
No doubt tat boy is a total loser, like all men who would be interested in a married woman. But... You've got to stop worrying about him. Put him out of your mind. He doesn't deserve to be there.
As for MIL, I would keep in mind that even though she may seem supportive, ultimately, it may be tough for her to hear/believe less than flattering things about her daughter.
Keep working on you CB
Bomb January 2012 - doesn't feel the same about me
~ "There is nothing love cannot face; there is no limit to its faith, hope, and endurance."