I was a single parent to one DC for 7 years (until met DH) .
Do you know I never thought about Christmases being different as a single parent until reading this thread! Was always busy and didn't think of it!
Normally had a Christmas thing at my work for everyone's kids.
We used to travel to grandparents on the day before Christmas Eve and stay until NY unless I was working.
Other things we'd usually do might be :
Hand delivering Christmas cards to neighbours / local friends in the weeks before Christmas.
Walking round to look at all the lights on the houses.
A lot of fuss about getting and decorating the tree- letting DC choose one new decoration each year.
Choosing and wrapping presents for grandparents.
Going and picking foliage, ivy etc and making our own wreath for the door.
Visit to a Santa somewhere- normally a nursery or school fair.
A walk with just us on Boxing Day and on New Year's Day,
A pantomime in the week usually
after Christmas.
Visit to a garden centre with Christmassy stuff going on.
Christmassy films on the TV.
Church either on Christmas Eve or Christmas morning.
Seeing my old school friends and their kids.
Normally playing board games just the two of us , or having a jigsaw on the go ( only do that at Christmas!)
It's not much different since meeting DH to be honest, except he's a better cook of roast things than me!