Good for you OP, freeing yourself from this toxic relationship.
My story is not so much outrageous stunts from my mum (dead now, not at all missed) but oh -- a thousand thousand cuts.
'Taking your successes for their own' - oh yes! 'I only want to hear good news' was the perpetual refrain good news re our jobs, salaries, promotions, grand children's successes, now we know that meant anything that could count as narcissistic fodder. But omg she was so useless when we were young and struggling with our own families. 'Been there, done that, got the t shirt' was the absolute sum total of our mother's empathy.
As other posters mention, big family events like weddings were definitely a cue for incredibly inappropriate behaviour as she couldn't be the centre of attention.
Our children missed out as the focus of our lives continued to be our mother. My daughter loved her grandma how could she know what perfect narcissistic fodder she was pretty, confident, private school, Cambridge. Her experience of my mother is that she felt valued even if her own mum was running around checking grandma was ok.
Is it a special narc thing to deliberately praise someone else for what you might be thought to want praise or affirmation for? So many BEAUTIFUL babies that were the children of strangers. So many CHARMING strangers, such WONDERFUL travel companions, table sharers, check out personel.
Later when I finally escaped my horrible narc ex (yes my life lived twice in service), she came to see me in the cottage I'd bought and all she could do was look around disparagingly and tell me endlessly, in mind boggling detail and with great intent how BEAUTIFUL a relative's house was ..
Once we met her at Gatwick, were subjected to a 15 minute tsunami of praise about a wonderful travel companion after which she drew breath, turned round and said 'no kisses? No hellos?'
We lived our whole lives in a world of blame. Until she died.
Appearance was all that mattered. We were trained to compliment her endlessly, and ask interested questions about her nail varnish etc. But there was no reciprocity. Only one person mattered. There was zero acknowledgment of the efforts we went to for her special birthdays etc. I suddenly saw this when for one event my younger sister transformed herself from
a middle aged dog walker into Audrey Hepburn. It was impossible not to react and I realized that my mother was deliberately withholding any acknowledgment of my sister's appearance.
Support was one way too. We gave. Didn't receive.
When she was nearing her 90s in order to clear the house a bit we had to endure lacy undies, teddies and basques (??) being held up for our delectation and stories told of their purchase and wearings. Grotesquely inappropriate.
She had to have help getting out of the bath which my sister and I were happy to do, but she loved to show off her legs and would flash them up out of the bath and scissor them around fishing for compliments.
You can see that my examples are not from my childhood. Like you OP it has taken decades to reach this clarity.
My parents had 5 children. On the surface people saw our posh house, my super attractive and sparkling mother, handsome Madmen type dad -- we children were dirty, emotionally and physically neglected. We've all had problems with alcohol and drugs.
Oh sorry should add we had some value where we could be said to reflect our parents. For example my elder sister was thought to have my father's brains. I was decreed to have my mother's looks. My little sister had my mother's hair. (Fucking unbelievable, isn't it) after that they couldn't really be bothered to ascribe any special qualities to us.
My narc mother was a truly awful person, a mother only in the crudest most basic sense, and I am glad she is dead.
Hope you have other support OP, and you can leave your mum behind and enjoy the rest of your life.