Wonderful advice everyone; thank you.
Re: my health -- One of you mentioned that he "gets off" hurting me and I had to chuckle, because that's exactly right. Also the bit about using my daughter as a pawn. You get this. I know you're right there with me. // The best thing for me is to move on from him in every way. I must give myself credit in this area: I only speak to him via text and about essential things, I've changed the photos in the house / boxed up his possessions / etc, I change the subject when mutual friends bring him up, and, very much unlike him, I refuse to talk about this situation around town. But I run into trouble in two areas a) every week with childcare issues (I learn what he's done and I can't help but get angry) and b) with the LGBT+ topic.
Regarding the LGBT+ topic, it's my own damn fault. I take full responsibility for reading the news and even (at times -- I have phases) actively reading gender critical blogs and news. I had same-sex relationships in the past and as a teenager was very active in promoting same-sex marriage here in the US… a lot of effort invested in this movement which now seems to have turned against me. That might be a good metaphor for what's happening to me internally when I read gender critical blogs. I just need to stay away from them for my own health. (I don't need unnecessary anger.)
Re: my daughter's health -- She is such a good girl. It makes me smile to type "my daughter's health" because I know she's happy and she'll be okay. :)
I often wonder how my husband developed NPD. He's the first grandson of a large, influential family. My sense is that the whole family manifests it to some degree. Cloistered, selfish groupthink. // As far as my daughter goes, she is the first grandchild, and she's been very spoiled by my in laws (ice cream for dinner, loads of toys, bedtime at 10pm, and they basically allow her to make decisions for the group both moment by moment and for the day).
So I plan to be the steady hand for my daughter: tell her the truth about sexual dimorphism, show her what it means to be responsible, teach her what commitment looks like, show her that identity and self respect come from working / contributing to a community, etc. But I also need to counteract to some degree the indulgence of my ex and in laws so that she doesn't become NPD herself. She comes home every Sunday, and it takes two days before she adjusts to her routine, discipline, and 8:30 bedtime. And I consider myself an very lenient parent… we practiced extended breastfeeding, baby wearing, bedsharing, etc.
I know I can do this! My daughter loves best to be home. She is a good girl and if I demonstrate responsibility and humility, she will choose the right path.
For all others considering divorce --
I can't say whether I recommend divorce. I am in the most difficult phase of it (adjusting to custody and preparing to give my ex my house) so my words are colored and skewed. Whereas in the marriage I kept a fantasy that things would get better, I now have no fantasies. Yet I prefer reality. In addition, you know what I have found? That I am as strong as I was before the marriage, that I am as free as I was before the marriage, and that I can dedicate my life to a higher purpose again … that I am more than a support structure for my husband.
Additional advice: Funnel away money early and often. Make copies of all paperwork (tax docs, retirement statements, etc.). Take photos and keep a journal. Enter mediation for the divorce if at all possible. If you husband is NPD, prepare for litigation. Divorce with an NPD is traumatic -- my husband considered it all-out war and pulled every stop (assaulting me, calling ambulance to the house alleging I was suicidal, took our pets and gave them away, you name it). You might not be able to control whether it goes that route, so get your ducks in a row. Splitting custody? I thought 50/50 would be okay; my attorney suggested every other weekend; I settled for 2.5 days a week. Ex has already lost interest. My daughter lives with my MIL who enables him; ex lives in another town. So I recommend getting as much custody as possible. You can always offer your ex to watch / visit your children on days assigned to you.
Melanie Tonia Evans on YouTube has a great video series on NPD abuse.
Also, I don't want to misrepresent all of these AGPs as visible monsters. What's so tricky about it is that I presume most of them are like my ex. He's a short, feminine man, always picked on as a kid. Very handsome. He'll go out of his way for anyone, really makes a great impression. Memory like a camera. He's outspoken and funny and his confidence is off the charts.
I understand why people root for him… that's what makes this so hard.
For the record, ex was US military and is now in IT.
Best of luck to you, ladies.