MB...I totally understand that it feels humiliating, but please know that no one thinks less of you for it. You did nothing except try to love someone who is very difficult to love. There is no shame in being loving.
None of us are perfect and we always have room to grow, but you are not to blame for your situation. You can't fix your H because you didn't break him. You can rationalize all day long about something you could say or do to make him better, but it probably still wouldn't work. You can't rationalize about something that's not rational.
You mentioned that H has some of the characteristics of NPD, but is not like that with his kids. What about previous relationships? The thing with children of NPD-ers is they are usually seen as an extension of themselves, and as a source for the NPD to feed his needs. The more perfect and wonderful they are, the better the NPD-er is able to feel about himself.
The thing to remember is, all disorders occur on a spectrum and various symptoms can occur to varying degrees. NPDs are capable of emotion, but they experience it differently than a typically functioning person. Their emotions tend to be reactive rather than active. They might feel positive emotions or empathy in response to something that happens, but they don't really initiate emotions. Because they are only reactive, they tend to be the type of people who can walk away from a situation and detach completely. If nothing is happening, they aren't feeling anything. They might be happy to see you when you turn up, but they aren't missing you when you're not there.
MLC *can* mimic some of the symptoms of NPD. The difference is whether or not there is a recurring pattern in the individual's life (such as a pattern of selfish behavior in previous relationships), or if this is all something new and alien.
Bottom line...it's not our place to try to diagnose your H, but just wanted to give you some food for thought and maybe something to talk about with your IC. People can come out of MLC or depression, etc., but personality disorders are pretty much forever.
