Baking and decorating Christmas cookies. I don’t remember my mother EVER baking cookies of any sort.
Gathering with friends to go caroling in a neighborhood. (I did that once as an adult.)
Gingerbread house building or contests. I’d seen gingerbread cookies, but never decorated one or built a gingerbread house.
Family or Communal Christmas tree decorating. That was always a grown-up’s job, usually Mother’s. Lights go on first after the strings were all tested, distributed ‘correctly’ around the tree, and then tested again. Then the hanging ornaments were hung, heaviest/largest near the bottom, smallest/lightest up near the top, so that hanging ornaments mirrored the weight distribution of the tree itself. And then came the tinsel, which HAD to be hung one strand at a time so each strand hung straight down individually. Heaven forbid the tree didn’t LOOK perfect.
Christmas balls/parties. What’s that all about, anyway?
Secret Santa gift exchanges. Again, what’s this about?
Many of these things I also haven’t done as an adult. I think there was a White Elephant exchange at a church group once, and a Secret Santa exchange at work once.
I HAVE had a couple nice Christmases, but they had little to do with my family of origin. I don’t even remember much about Christmas when I was married and the kids were around.