A bit of background…
For more than 10 years, my partner and I have taken turns spending Christmas with my family, their family, or just the two of us. We sometimes see family on our own or together on Christmas Day, but I'm easygoing either way since we regularly see each other and our families. Generally, I prefer to be together on Christmas Eve and usually spend around 3 to 4 hours with my family nearby on Christmas Day, sometimes swing my partners family later in the day.
Lately, I've been prioritising time with my older and smaller family because time is running out, especially since my partner has a larger, younger family.
It's worth mentioning that we're going on a 5-night holiday with my family in the new year again, because time is precious.
A few weeks ago, my partner mentioned they planned to spend Christmas Eve and Christmas Day with their family on their own. I felt disappointed as I'd rather have spent most of that time together. After expressing this, my partner agreed to visit their family just on Christmas day instead (leaving early in the morning to help with the cooking) and I thought that was a better arrangement.
Yesterday, my partner casually mentioned they they were sticking to the original plan of spending the full two days with their family. I got upset and explained again that I thought it was unreasonable. Looking back, it might not be a big deal, but at the time, I wasn't happy, especially because I thought we had already planned and agreed on things.
So am I being the arsehole here? Is disappearing for the whole of Christmas to see your own family not a problem because your are going on a holiday with your partner and their family thereafter? Or is it reasonable for me to be frustrated?