I lost my husband five weeks ago. It's going to be my first Christmas on my own as well.

Maybe I'm lucky that we didn't turn Christmas into a big event for several years? So, I am not planning to meet anyone, I'll stay at home and see what food I feel like cooking. Binge-watch TV, maybe some DIY, house-cleaning. Talk to the box with the ashes, like most days (scattering the ashes won't happen until the spring, I want to wait until my husband's next birthday).

Yes, I do enjoy looking at a pretty Christmas tree... but I don't feel like setting one up or putting other decorations up ... and I wouldn't want to do it just because someone would be upset or someone advises. They can't be inside someone's head and decide what works and what doesn't.

Basically, my thought for you is: don't feel you have to copy any solution that has worked for others. Don't feel you have to replicate a standard of celebrating Christmas that used to work for you in the past. Everyone is different; change the parameters of celebrating Christmas if recreating the old Christmas is painful.

Maybe make plans for deliberately doing something different, not even Christmas-related, at least for some of those days? Maybe there's food that you always wanted to try? Make plans & do research for trying out a new hobby? Some craft project? Books to read? Go for a walk and take photos? - It could serve two purposes: help you look ahead and also provide distraction.

And... I think it's also OK to have "wobbles" inbetween. The advantage of being alone is that you don't need to worry about upsetting others! Cry for a bit when you feel like it. I cry when I look at photos for example; it's pressure relief. After that the focus is to looking ahead again.