You have my deepest sympathy. I've just had a horrific flu but I was far more terrified of getting post-viral fatigue as last time I had it for three years. (Tried to push through instead of rest - serious mistake.)
You are doing the right thing.
I would:
Get a pile of fresh clean PJs, socks, underwear and loungewear ready in advance. Clean dressing gown, bathrobe, towels and facecloths too. Get DH to help you change the bedding before he leaves.
If you haven't already, stock up on Vitamin D spray, B12, iron and any other vitamins you might be low on. Also something like Actimel and keffir yoghurt to try and rebalance the gut bio.
Get some good quality ready meals and low-prep festive food (good cheese and crackers, easy peel clementines, smoked salmon and cream cheese with bagels. Also your favourite teas, tisanes, coffee, hot chocolate etc. And some bamboo plates and wooden cutlery.
Before they leave, ask DH to get a big bunch of really cheerful flowers or a colourful plant or two and place them with some candles in spots around the house that often catch your eye. Maybe ask DC to put up some fairy lights for you.
Get some very luxurious bath products - maybe as Christmas presents form DH or family.
Get a pretty water jug and glass and put them by your bed. Maybe a tea tray and mini kettle in your bedroom.
Stock up on easy to read good books on your kindle or audible or paperback.
Set to record half a dozen films, comedies etc you'd like to watch.
Buy some bird nuts or seed.
Then each day just let yourself sleep late. When you get up, if you can manage a bath or shower at some point do, then change PJs and just watch a film or read or listen to a book. Snack on the healthy food. No washing up - chuck the bamboo plates away.
Throw out some bird seed so you can watch the wildlife for some company and also if the weather is mild, sit by an open window or kitchen door. When I was too shattered to leave the house I loved getting fresh air this way.
There are some nice super gentle online yoga exercises for bedbound people - those might be nice to try.
Zoom calls with family every day if you can. Otherwise, focus on getting better.
If you can manage a very gentle walk - just to the end of the road and back, do that. Or sit in the garden for some vitamin D.
Let these 5 days be a proper restorative convalescence in which you do no laundry, cooking, housework, but still have fresh clean clothes and bedding, good food, uplifting entertainment.