So sorry for all those with bad or unhappy memories, especially bereavements at such a time.
My worst isn't that bad, but it was v upsetting. My mother was in the earlier stages of dementia, and was supposed to come to us for Christmas as usual, with sister and niece who were visiting from US.
Shortly before I went to pick them all up on Chr. Eve - 60 miles away - my mother phoned to say she was sorry, but she really couldn't cope with a lot of people, noise, and fuss - she'd rather stay quietly at home.
A shame, but OK if that was what she wanted. I took down her presents and some nice food, brought sister and niece back here.
Roll on a few hours - everyone else was out, taking niece to see the latest Harry Potter or some such, and my mother was on the phone, furious. What was she doing all on her own on Christmas Eve? I was a terrible daughter, she was cutting me out of her will,! etc. etc.
It was no earthly use trying to tell her that of COURSE she'd been invited, she hadn't wanted to come! She simply couldn't remember. I offered to go down then and there to pick her up if she'd changed her mind - no, she didn't want that either, banged the phone down, so angry and nasty.
I was in tears for ages, it was so upsetting.
Thank God, by the next day she'd forgotten all about it.