"Betrayal is betrayal" - saying stuff like that is closing the door to nuance, which is exactly the problem I tried to bring up. The man who has been taking care of his wife with dementia for 20 years who doesn't even recognize him anymore might cheat just like the woman who's husband can only get off with hardcore porn and isn't interested in real life sex anymore. I'd say these cases are very different from each other and all the other millions of scenarios I could come up with. I find it much more interesting to find out why people do things, rather than always going back to yeah but you shouldn't have.

Saying we should be honest with ourselves and others and communicate is nice, but we're not teaching people how to do this. And too often the focus is on judging the action, rather than encouraging the person to figure out the true reason behind it so learning and growth can occur.