I know you've thought a ton about your sitch, but have you ever thought that to an "it's all about me" person, the reason they have trouble relating to a generally good, thoughtful, giving person is that they can never have empathy for that person and that's what makes an A so intoxicating to them? That there's another person EXACTLY like them?
It's funny you should say this, H4U, but as I've just started reading more about NPD, this is EXACTLY the impression I was getting. You are NOT going to be much (if any) remorse from a narcissist, for example.
There's also a big correlation between NPDs and infidelity, and SERIAL infidelity goes thru the roof with this group.