I don't know if you recall me talking about my dad and an EA he's having. I still don't believe the woman he's infatuated with has a clue, I truly don't....I believe she views my dad as a father figure (she's my age). But the fact is this as I see it.....you may not be sexually attracted to this man, but you do not know how he feels about YOU. You should not be confiding things about your M to this man.
Put yourself in your H's shoes on this. Your a man who has a W who is now spending time talking with a younger man, that she met while the two of you were separated, and she's telling him things about your M. How would that look to you? How would that make you feel?
If your H were to tell you he doesn't like you seeing/talking to this guy, then that could make him look controlling....so instead he plays indifferent to it.