I would suggest the following:
1. Organise a lovely day alone with special treats from her favourite food store.
2. Volunteer at a local Salvation Army or homeless organisation which is offering help at Christmas
3. Go on an organised coach trip to a hotel fir the festive break,
4, Invite another single person to spend the day with her, plan a walk, pack a picnic plus Prosecco etc
Then later, have a day with the friends who were not available
It can be a lonely time even in normal circumstances but we have to be inventive and creative to cope with what is being thrown at us. Where is she based?