So the tree is down and the decorations are back in the loft; your cards are now stuffed into the recycling bin and all that's left to remind you of Christmas are the few remaining Quality Street sweets that nobody likes, a scary credit card bill still unopened on the mantlepiece, a pair of jeans that are too tight to fasten and that small pile of unwanted presents in the corner awaiting further notice.
Meanwhile, the weather outside is frightful, money's too tight to mention and your body's gone cold turkey from all that cold turkey.
The first week of January is always the most depressing week of the year, and that's pretty much official. So how do you pick yourself up and make the best of a bad job?
My annual three-point plan of action works every time and so I'd like to share it with you, especially if you're struggling with a spot of seasonal readjustment disorder of your own.
Chopping up the tree
I always buy a real Christmas tree every year and, because it can cost anything from £30 upwards, I always make sure I get every penny's worth out of it. So after the decorations are down and the house is back to normal, my boys and I spend an evening chopping it up into firewood and filling the house once again with that delicious scent of alpine sap.
First we snap off each dry, brittle branch until we get to the bare trunk and then attack it with a saw.
(And if you don't have a real tree, simply nab one from a skip or a tip. They're everywhere at this time of year!)
Making a bird cake
Being a life-long nature lover and perennial twitcher, I love to treat my feathered friends to a special festive feast and to watch as they descend in their twittering masses, so I always save the post-Christmas scraps especially for this purpose.
Here's my tried and tested recipe:
Take all the dried-out mince pies from the back of the fridge and crumble into a large bowl. Chop up all the nuts left over from the holiday season, add the dried fruit and figs that no-one ever eats, but you always buy anyway just because that's what you do at Christmas, and mix well.
Grate the Stilton cheese that you bought for the same reason and combine thoroughly.
Add the Christmas cake your Auntie Ethel bakes lovingly for you every year because you don't have the heart to tell her that no-one likes or ever eats them.
Pour over the congealed bread sauce that no-one ever touches because it looks and tastes like wallpaper paste, and mix thoroughly.
Press the mixture firmly into a baking tin and leave to set in the fridge overnight.
Bon appétit, mes oiseaux! Believe me, it may sound disgusting but they can't resist it, and it's wonderful to watch who or what you can coax into your back yard on a dreary January day.
The trip to the charity shop
Everybody gets them - the autobiography of a celeb you never did like and like even less now since reading the back cover; the bath salts that make your eyes water; the hair straighteners that you got despite having naturally poker-straight hair; the slippers that are so big there's room for an extra foot in each; and of course the ubiquitous Christmas novelty socks ... if only we weren't too polite to ask for the receipt!
In the spirit of one-man's-meat-is-another-man's-poison, and vice versa, every year at about this time I set an afternoon aside and head off to the charity shop with a group of friends in tow, all bearing unwanted gifts. But here's my secret...
Wait until after the Epiphany tomorrow which is the traditional deadline for all things festive to be removed from sight and stored away. More specifically, wait until this Saturday afternoon. In my experience as a bargain hunter par-excellence, this is the absolute optimum few hours of the year for uncovering a total treasure trove.
But hurry: by the time you read this I might already have my beady eye on the best bargains...