I hear this very thing from H. I also hear "If we are happy, the girls will be happy." Blah blah blah I agree with you that the kids might be fine in spite of the divorce, but yes, its pain and heartache that is not necessary.
When I R talk with H, I try to 'remove' the kids from our discussions. Because I think we all (you, me, your W, my H) know that kids are the most important here, they are the ones we'll have to watch out for, etc. But I want to know what my H wants, what will make him happy. These things (him being happy) will make him an even better parent.