Mostly, I just laugh.
I moved out the day I turned 18, because my parents are mostly narcissistic assholes. Like, for no reason either. It's basically like they sit around all day thinking up ways to fuck with their kids.
Anyway, after like 7 or 8 years of that, I started talking to them tepidly, you know, like Xmas and Easter kinda shit for a couple years. Then they kicked my sister out of the house because she had the decency to call them and say she was spending the night at her BF's. She was 22 when this happened. But nope - not coming home? Just move the fuck out. I took my sister in, and told them I was done dealing with their shit. That was....15 years ago now? I think so. Haven't spoken to them since.
Anyway, Im sorting thru the mail a week or so ago and I see cards addressed to both my daughters in a familiar handwriting. Told my oldest to open hers, Christmas card from my parents with $50 in it, and "Sorry we've missed so many Christmases"
Okay. Fine, it's a start. Except - both the kids live with me. They have to know id get the mail and see them. Anything addressed to me? No. Note saying "hey, sorry for being collosal fuckups, but we're old now and are regretting our lives now that no one wants anything to do with us."? Nope. No call, no text, no nothing. Just comical. What are you hoping for to accomplish with this?
Thankfully my oldest had the correct response. "Well, I'll take their money, but I have no interest in having a relationship with grandparents that have no interest in having a relationship with my father."
100% sure that the problems in the world are all caused by boomer parents. I seemed to have raised my kids right and done well by them, but God fucking damn, my parent's generation is just fucked up.