To be annoyed that my friend is annoyed over my non attendance at her party

[Daisysbear]

A friend of mine is celebrating a big birthday next month and is having a party on Boxing Day (big afternoon affair). As a family we traditionally get together on this day, have a nice meal and take the children to the local pantomime i. It's something we've done for years, ever since the older grandchildren (now in their twenties) were tiny. I don't want to miss it, particularly as my parents are getting older and I'm really conscious that our Christmasses together won't go on forever.
So I've turned down her invite and suggested I take her out for a meal in January instead. Apparently she's really annoyed with me and thinks I could miss our family tradition for one year.
AIBU to think, if you arrange a party for a day so close to Christmas, you have to expect that a lot of people will have family things they are obliged to, or would prefer to, attend?

oh the irony of having a meal with her family on her birthday, but wanting to deprive you a meal with your family...

Oh get over yourselves with the 'nobody over the age of 20 should have birthday parties' schtick. Nothing wrong with a party to celebrate the passing of the years and being plied with champagne and being told how splendid one's looking.

And in all honesty the reality of Christmas is such that plenty of us would run madly for the door on Boxing Day, clutching our invites/escape tickets, and dance happily on tables surrounded by friends into the small hours.

nothing wrong with a party.

everything wrong with a big diva-strop because somebody doesn't want to come.

I had a friend throw an absolute wobbly because I didn't go to her last minute birthday celebration in the pub because I'd made plans to go to someone else's 30th months in advance. I had an 8 month old baby at the time and had nights out very rarely. I apologised and took her out for a meal a few weeks later, and she proceeded to get drunk and have a massive go at me because she'd Twitter stalked the guy whose birthday I had attended and she thought I only went to his party because there's be famous people there (there weren't, fuck knows why she cooked that fantasy up) and obviously I'm not allowed to have other friends.

YANBU.

YANBU

Your tradition sounds lovely and takes priority. You don't have to justify any part of this.
Your friend should be more understanding.

DH'S birthday is around Christmas and is well used to people having other plans. Therefore, he held his 30th exactly a month later in January. It was great, most people were able to come and it brightened up what is usually a very dull month.

YANBU