Nons being called 'nuts' by NPD partners

You are nuts. Questioning anything she does is like saying the world is flat - and that it doesn't revolve around her. You see, in her perception, disagreeing with her or seeing anything wrong with her is clearly irrational, because she is without flaws. She lives in another world. In that world, you have your role, and you are failing to fulfill it. You haven't accepted her skewed perception, so you are out of touch with 'reality' and need therapy to set you straight. (Also, if she is more sinister and deliberately manipulative, then having you seek treatment, and therefore be crazy, is ammunition for her: you can't be right, you're crazy, you're in therapy. Any unflattering thing you say about her must be the product of a deranged mind.) Anyway, she has done nothing wrong. A different set of rules applies to her. She ignores you when you have done something wrong; and that is to expect her to follow the same rules that apply to you.

She is your fiance? Good! Then you are not already married. You still have time to escape. If you think you can get through, to prove she is wrong, to make her empathize with you, then you think she can be someone other than herself. Good luck with that.

Your best bet is to dump her. Or, if you have a lot of patience and don't want to be the one to end it, change your own behavior. Stop apologizing unless you have actually done something wrong. Do whatever you want to do, and if she protests, do it more. Spend less time with her, and talk to her less often. If she does something wrong, "beat her to the punch" by ignoring her first. Tell her she has done something you disapprove of, and for the next few days, don't say anything nice or give her any affection. If anyone apologizes, it will be her apologizing to you. Let her know that you will not be walked on. She will either change her behavior or dump you. The reason the relationship has lasted as long as it has is because she knows she can get away with treating you that way.

Here is an idea. Agree that something is wrong with you, and tell her you need some time apart to work through your issues. Get away for a few weeks. See if this changes your perspective.

"NPD fiance" - that's kind of an oxymoron isn't it? I mean, how can you recognize that she is NPD and still be engaged to her? Guess what? If you marry her you are nuts.