I have opted to be single forever because of these precise issues. The fact is that the men who have come into my life have consistently made it worse in some way - never better - and most often completely unlivable. I don't think men will truly get it and grow tf up until women refuse to allow them to be a drain on our mental, emotional, and physical resources.
I understand why women stay married - especially the financial reasons - but I have a feeling you'd realize just what a drain he is on you if you ever got away.
I'm not trying to be harsh, just realistic. And no, these betrayals never do get forgiven - not because we're mean grudge holders - but because the continue to happen. A complete 180 in behavior would have earned him forgiveness a long time ago.