I wanted to comment on this, @Theydontwantme because my father was almost certainly NPD (he was sectioned in the end after it all went horribly wrong). My mother also has some difficult behaviours although I'm not convinced narcissism is her main problem. First off, though, I'm sorry you're going through this. Realising that your parents aren't that interested in you is really hard. It makes you rethink your whole life. I was estranged from my father for years and I'm LC with my mother.
My father also used to tell stories about how everyone thought he was amazing and clever and talented. How they envied him and wanted to be just like him. How they could see his specialness and we (his family) were dicks for not realising how lucky we were to be related to him. It took me a long time to be able to see it, but it was all a lie. No-one thought he was special or talented, they mostly thought he was an arrogant prat and a bully and avoided him. He had a few friends but they were all absolutely awful people. He talked himself up constantly, told us all he was so amazing, he was just so creatively talented (despite not producing a single piece of creative work in twenty odd years - this was, apparently, our fault because he couldn't be expected to create with such an uninspiring, unsupportive and boring family). I never heard ANYONE outside of the family say that they thought he was clever or amazing or talented. The only person who said it was him. It never made any sense to me because there was no evidence for any of it, but my mother fell for the bullshit hook, line and sinker. She spent years, and I mean YEARS of her life trying to convince him that she was worthwhile and just as good as other people, trying to figure out how to get things 'right' so he would finally be pleased and be happy. But she was never able to, because there is no 'right' with someone like this. It was almost like she had a pathological desire to win the game and couldn't let go until she had.
It is OK to walk away from a narc and be the loser. Let them think you're the loser. Let them tell other people you're a loser. You don't need to convince them otherwise (you can't anyway, because the goalposts constantly move). It's OK. Let them think they've won, whatever that means.
But I also know how hard it is to realise that you're not that important to your parents. My mother has shown me that time and time again. I get attention if I'm useful but other than that she's not really interested in me. She's not interested in me as a person beyond what I can do for her. It can sometimes be really lonely. I stopped trying a long time ago, tbh, though I don't think she understands why. But I won't beg or perform for her attention any more. It's not worth the price.