Another Christmas avoider here. I go away now for three weeks but in the past that was out of the question financially or time wise.
No kids/partner back then and parents had died within 2 years of each other. Family very welcoming but I hated the faux jollity and far too many babies, bottles, buggies, bags, toys and a massive headache!
So one year I said no thanks. Well I could not believe the pressure I was put under to join in and not be on my own, which was all I bloody wanted! I gave in, regretted it again, and the next year just visited everyone second week Dec and hibernated from the day I finished work up to Boxing Day. It was fabulous!
The trick is I think to remove every vestige of Christmas from your house, TV, radio, avoid shops, no Christmas songs and so on. Ordinary but very nice food not Christmas fare. I don't drink but I suppose a bottle of fizz would be good too.
Then I watched YouTube on the TV + older series on Netflix that were NOT Christmas related.
I can tell you folks, that normal service resumed and no one cared what I had done really!