You're asking the wrong question.
The question is "Why am I still trying to make him care about things that he clearly doesn't care about?"
You've listed a string of 'consequences' that he has experienced but most of them are actually consequences for you and other people.
He has lost me.
This isn't hurting him (except for the loss of whatever services you were rendering him in the first place ) because he wouldn't have cheated in the first place if he cared much about losing you.
His beautiful, now adult, children view him with contempt; they tolerate him at best.
This isn't hurting him much apart from the fact that he feels entitled to respect regardless of his actions. He doesn't care about the loss of the relationship because the relationship was never very important to him in the first place.
All the things we were supposedly working towards have evaporated.
I expect if you think honestly about this, they were mostly things you were working towards and he was putting in whatever minimal effort he needed to in order to avoid outright conflict.
Every memory of past things we did together, firstly as a couple, then as a family is clouded; I can barely remember them now because I must re-envision them based on the man I now know him to be.
This is exclusively your pain.
Yet he still maintains that he is not a 'bad' person.
He says this because this is what he actually thinks and the sooner you accept that and act in accordance with it, the better.
He thinks doing what he wants is fine, and likely wouldn't care much whether you were sleeping with prostitutes too as long as he could be assured that you wouldn't stop providing whatever services he expects from you and wouldn't embarrass him publicly.
You are dealing with a person who doesn't care much about outcomes for other people. He is only interested in outcomes for himself. And he expects everyone to behave in fundamentally the same way he does. He can't understand why you care so much about other people in the same way that you can't understand why he doesn't.
You are trying to avoid accepting that the world is not the safe and logical place you want it to be. You want to believe in a world where people can be taught to see 'right' from 'wrong' if only you present it to them in a certain. You don't want to accept that what you see as 'right', some people will see as 'wrong' no matter how you explain it to them, and what you see as 'wrong', some people will see as 'right'.
This is what we call 'the human condition'. We are all different, sometimes far more so than we want to accept. The ideal of all people living together in perfect love and unity is as far removed from reality as the nightmare of all people descending into total chaos and anarchy.
All you can do is find your people and stick with them. This guy isn't one of them.