I stopped having "xmases" is my early 20s because of toxic family making it unenjoyable. I've spent most xmases since then doing volunteer work, petsitting, or occasionally just doing nothing.
It's honestly just a date in the calendar. The only thing that makes it hard is the comparison. I know it makes me feel horribly sad and lonely when I see other families just having a nice xmas together like normal people, knowing I can't have that.
So, doing something different where I am not exposed to seeing "happy families" too much really helps. Also, doing something nice for other people makes me happy and grateful and also helps a ton. I mostly enjoy xmas for that reason now and only have a few moments where I wish it could be different.
There is also a #JoinIn hashatg on Twitter/X over the festive period where you can chat with other people who might feel lonely at xmas. I have had a laugh doing that as well as cool conversations. It was started about 5 years ago and as far as I know it's still running. So even if you're stuck in the house or ill, there are ways to cheer yourself up and not feel so alone.