FWIW - I think that some affairs are deal breaker while others may not be. I can't say what I would do but I lean toward deal breaker. That is why I tend my fences despite these issues. If I go outside my M, it means I am out.
I'll add that all of this dealbreaker stuff would also be a dealbreaker for me IF I didn't have children. I guess in a sense I'm viewing it as "the family" trumping "the M." But not really, because if I couldn't be happy in the M, I'd probably want out. I just don't know. I'll respond to the rest in another post.