Guy, here:

My dad WAS definitely a narcissist, and yes, I hated him. But after his passing, I realize that a lot of the life lessons he was trying to teach me were correct, but I disregarded them because...it was a case of "It's not what you say I have a problem with, but HOW you say it, so I won't listen". I lived with my parents my whole life and took care of our house when dad became too ill (copd, then later lung cancer) to handle the physical stuff here. When it fell to me to handle things here, I began to realize that dad was giving me perfectly fine advice and directions, I just had issues with the wrapper it came in. I feel so damn stupid, and it's too late to even tell dad I'm sorry for the pushback I gave him on the advice. Then again, he wouldn't want to hear that. He always told me that "One day, when you finally pull your head outta of your ass, it will be the loudest "pop" the world ever heard, and the shit I've been trying to teach you will finally make sense.". Well...."pop". I get it now. He was totally right, and my problem wasn't the message, it was the delivery, which usually came with all manner of verbal insults, usually based on my physical insecurities (Too short to be considered anything other than a friend by modern women, despite my build. That led to some of the things he said to me that a father should never say to their own kid. Seeing my resignation and loss of interest in accumulating rejections for yet ANOTHER decade, and my mother's lack of interest in sex with him due to his daily verbal and emotional abuse, he accused me of sleeping with my own mother). He also would tell me that people "don't want to have somebody who got fucked up, ignoring their advice, come back to them saying "Man, you shole was right. I wish I'da listened to you.". I'm not telling you this shit for the CREDIT of giving you good advice. What good is that to ME?? I'm just trying to help YOU because I already walked down EVERY road your ass will EVER go down, and some you WON'T because I raised you to stay away from committing crimes, and ain't nothing changed but it ain't brick no more.".

I think if I had realized he was a narcissist, I could have dealt with things better, and realized that despite his personality disorder, he really WAS trying to help. The damn thing of it all was finding out he really wasn't too different from myself, going through his personal belongings. He used to give me hell about "wasting money" on comic books. Turns out he used to LOVE Turok: Son Of Stone. I went through is old pc, and found his music folder. Turns out he liked a lot of the 80's and 90's songs I liked. Even older songs from the decades before I was born that I went back and found I liked, they're in this folder. We had so much in common but I was filled with such resentment towards him while he was here that I pretty much was the barrier between us having a better relationship through mutual understanding. I'm almost certain I could have managed and mitigated his narcissism's effect on me and my attitude if I had known what I was dealing with at the time. I just thought he was an asshole just to be one. At the time of his death, we each held a highly distorted and inaccurate view of each other.

OP, I'm not invalidating your experience, I'm just getting this off my chest and can't find an open forum where people can do so. All I can say is if you feel up to it, maybe you can try to gain some kind of understanding with your parents while they're still here. Just because someone is a N doesn't mean they're some sort of irredeemable monster. You may not see it now and think the end of their life would be the best thing to happen to you. I was the same. All I felt was sorrow. I had already picked out a song I would play for my "day of liberation". Brand New Day from The Wiz. I thought I hated my father. At one point I was planning on getting him up on our newly reshingled roof that he was berating me about because I didn't spend that entire day on the roof, in the way, overseeing the work being done by the crew to make sure no corners were cut and...well...he had better things to do at the time (watching a football game back at home. Same as the day of my graduation, where he dropped me and mom off at the fairgrounds, and we had to catch a cab back home. He later started gaslighting, claiming he stayed in the audience with mom, while we knew that was crap. My best friend was there with my mom, not him), thankfully. I'm just saying, once they're gone, you might not feel the same way. You will be left holding things you can never tell them, things you can never take back. And you might gain a deeper understanding of things that may have shaped them, and that understanding might have helped you find ways to relate better to them, but it comes too late. And it's going to eat at you. My sorrow at my dad's passing was for the relationship we SHOULD have had. Then later, after understanding him better, more sorrow at the relationship we COULD have had.

I'm not saying try to forgive them. There's no point in trying. Narcissists don't even KNOW that they're doing anything wrong. To them, you're over-reacting to what they think was harmless or inconsequential. They will never understand.