I think the truth is that he was never going to make her happy, because they never should have gotten married. She didn't want to get married! She clearly does not want to be married to this man. He knows she does not want to be married to him. Their open marriage is about not wanting to be married at all, but feeling obligated because they slept together when they were very young and foolish, then she happened to get pregnant. She was strong-armed into the marriage, which he probably knew on some level but didn't think twice about in the moment. Now she regrets never having experienced her "foolish twenties," and who could blame her? He seems like a traditionalist, she's obviously not. He doesn't seem to want her, so much as A Wife. It's all a mess but it never had to be.