MamasMa,
You can both make your own tree using any Christmas cards you receive, and if you don't have enough, cut out pics from magazines, or draw your own and arrange on a wall using blu-tac (see pic).
*Create a 'gift' box.... Find a a box that will hold a few postcard sized pieces of card/paper. Cut out small pieces of card (old xmas cards are good for this) and write 'to do' gifts on them that you know she will like, and let her choose just one a day - EG:..........
Baking gift simple biscuits together that she can decorate - icing and smarties always did it for my boy. Edible glitter anyone? Take pics before they all get eaten.
A winter picnic in the park gift (take a flask of hot chocolate and some little sandwiches, perhaps). Collect 'treasures to take home and put in a bowl to be talked about and admired.
weather gift . If it's raining go puddle jumping, plus stand an empty jam jar outside to collect the rain to see how much fell. Windy - make flags using some cloth tied to a stick and go outside somewhere to make them flap. Or streamers - approx 10 longish lengths paper - magazine/wrapping/whatever, all glued/selotaped to the top of a stick. Run around outside with them to watch them shake. Snowy - take a stick and draw patterns/ pictures in it.or just stomp up and down to hear it crunch underfoot. Take pics. Go inside and draw snowflakes or cut out of paper.
Make bunting gift - a piece of string, some fabric - or paper which can be decorated. cut out some longish triangle shapes(2 long sides, 1 short side). lay string along short side with a fold over allowance. Fold over and glue down. Decorate the house!
Write a very own story gift- have a blank note/scrap book with just a few pages in - maybe 10. you start the story and write a short sentence in the 1st page - eg - yesterday I put on my big boots, went to the allotment and dug up a carrot/treasure box/ old spoon. etc.
DD then adds her contribution to the story on the next page. You can both draw amazing pics all the way through it. (Doesn't matter if bits of stories she's already heard get added in).
Maybe 5-6 'gifts' in the box, but only one can be taken out each day. But by the end of the week she should have a collection of very special gifts that will hopefully inspire other things to do.
You've probably already thought of these 'to do' things, but I remember doing these and other, similar activities with my boy, the 1st xmas we found ourselves alone.
I don't remember how cold the house was, or that we had cold meat, chips n beans for xmas dinner - honestly!!. I just remember the fun we had....and I've still got the story we wrote together, several decades later.
I hope it helps 
Ps - glitter is conditional..........on everything!