I am really sorry for all of you that had to experience such awful behaviour from parents.
I cannot say I have had a narcissistic parent myself, but my husband's mother surely cannot see beyond herself.
It took him until adulthood and having a family of his own that he realized his former version of a normal parent/child relationship was anything but.
My MIL is spiteful, selfish, and self-centered but would flip everything around and try to make it seem that her wants were what was best for anyone who disagreed. She wasn't verbally abusive but used money to control her sons until they broke away. For us, she thought giving a "gift" of a downpayment meant she could come and go as she please from our home, arrange things the way she liked, give countless unsolicited "suggestions" that she actually checked to see if we followed up with. A chain smoker imo, even getting her to wash her hands before holding our newborn was a struggle. She simply knew better than us and every health agency in the world. The guilt trips never ended. Wanted to control aspects of our parenting as well. Decided for herself that she would be our childcare, even though she was never a consideration. Made my husband feel awful for setting boundaries. When things broke down, she shared "her side" with as many people as she could to get them onside.
She has always had poor relationships with female relatives, partly because she sees them as a threat. Her mother, her MIL, both DILs. She cannot see the common factor in these conflicts. She overstepped and made far too many attacking comments to others about us as parents before my husband decided to end the relationship with her. Manipulation and alienation were her go-to plays when her boys were growing up. FIL is wrapped around her finger. My husband refused to allow her to be in a position to eventually pit our children against us.
She does not have a close relationship with the son who still keeps occasional contact, yet she projects this relationship as close because everything is about appearances with her. This son has not physically seen her in God knows how long, with no immediate plans. We love him but have had to stop him from relaying the negativity from her about us. Apparently she is still selling her story that I "stole her son" and he is being "controlled". They reality is that I was her only hope of mending the rift at one point. I do not pressure my husband to reconcile at all now.
I like to leave the diagnosing to the people who studied years to become qualified to do so. However, even without the most abusive behaviours that so many of you have suffered, I'd wager my MIL would also be diagnosed should she gain the self-awareness to seek professional help. There are definitely spectrums of abusive behaviour.