Today is November 19 so most of us are nine days into our “Christmas party diet”, right?

What do you mean, “no”? More than half the country’s females are supposed to have started slimming on November 10 to fit in to their statement party outfit and be “the envy of their workmates”. It says so here in this survey by British Lion eggs.

We’re all gearing up to “glide into glam” with some sequinned accessories and this season’s “must-do up-do”, aren’t we? To go from “Nought to Sexy in five minutes”. To “shimmer, shine and dazzle”. To follow the “Ten Steps to Being Party Perfect!” (© all glossy women’s magazines everywhere).

All right then. No, we’re not. Because the only party to which most of us will be invited is our work do and this will probably involve drinking Cava served at room temperature while standing between the office water cooler and the bin and wearing the same trousers we’ve worn all year though perhaps with a “fun” bit of tinsel in our hair.

And the thought that will kill us as we stand there trying to “whoo!” ourselves into a vague state of gaiety is that somehow, somewhere other people are having a genuinely fantastic festive time flitting from glamorous shindig to red-carpet soiree with a brick of cardboard invitations under their arm and a regalia of cocktail dresses to choose from. And we will want to sit down amid the discarded streamers and weep.

Well, dry those tears. Because the Christmas party season is an illusion. It is a charade, a myth, a fantasy invented by magazines and the marketing industry and perpetuated by smug TV ads to feed your inadequacy and make you feel that if you don’t rush out and buy another must-have frock with ruffles and matching metallic clutch bag making this your “hottest Christmas ever!” then you are a loser who deserves to die. (No, I haven’t had that many invitations thus far this year, as it happens).

You know that feeling that university students get, that a better party is always being had elsewhere, and that they are perpetually NFI? But then it turns out that all the parties were rubbish and everyone was secretly wishing they were at home? Well, that’s the Christmas party season in a (wal)nutshell. What drives the entire adult yuletide industry is precisely this dynamic. And yet millions of us buy into the con, just as we bought into the mass peddling of the US-imported merde that was Hallowe’en.

There must be women everywhere who followed the mantra and now have wardrobes full of spangly off-the- shoulder frocks with not a single place to wear them.

Did you know that John Lewis — and I can scarcely bear to type this — is holding consultations throughout November and December to help women to learn The Party Rules — that is “the bible for nailing down the office Christmas party look”?

I like John Lewis. It numbers among my favourite shops, so it upsets me that it countenances such bollocks. But there’s more. There are Mr and Mrs Makeovers to strengthen your man’s dress sense for the, yes, “party period”. The party period, note, seems to include time spent in your own living room farting in front of Morecambe and Wise.

“For many women Christmas lunch is the event to impress family”, it says, suggesting a vintage floral tea dress for a smart-casual approach. Impress family? Mine wouldn’t notice if I was naked save for a fig leaf fashioned out of turkey giblets.

Apparently you should “make your mark at the office party” by sporting the season’s “in colour”. I think that colour might be purple. But then again it could be gold. Or black. Never mind. It doesn’t matter. Because it turns out that most office parties have been cancelled anyway.

Yes, the irony is that, despite the continuing delusion that we’re all in a festive social whirlwind, this year, according to a poll by YouGov, fewer than four in ten workers will be getting the chance to groove on down next to the Xerox machine or fend off a bore with a sweaty top lip, which means the pretence is even more flimsy than usual.

A great many employers won’t stump up the cash for a bash, either because they can’t afford it or, if they are a bank, because the sight of some legless City boy spewing a £200 bottle of Cristal on to his shoes while a family sold a bad mortgage in Darlington prepare to move into bed and breakfast accommodation mightn’t be helpful PR.

Of the few who will get a party, one in six will have to pay for it themselves. Even the BBC has abolished the £25 Christmas party allowance previously allocated to employees (well, to be fair, there can’t be much left in the petty cash after all those executives’ taxi bills). The headlines shriek: “The party’s over as firms cancel Christmas”. Really? Crack open the Lambrusco! Because, and I hate to break this to call centre bosses and paper firm managers of the nation, but quite a lot of people dread the Christmas bash.

Despite what glossy mags tell us about it being the highlight of every employee’s year and for which outfits are planned months in advance, a great many of them are relieved when it doesn’t happen. An acquaintance who works in a large retail-based company says the workforce practically did a jig when the news was delivered to them.

“So many people have been made redundant and there’s so much tension crackling round the office someone would probably have got decked anyway”, he said. “We just can’t be bothered with the fake jollity this year”.

I know it’s bad news for hospitality companies but think of the upsides. No worrying over whether your outfit is too slutty, whether you made a drunken arse of yourself, whether you were mouthy with the boss, whether you might be sued for inappropriate bottom-touching.

Most British festive celebrations these days can be condensed to two bookend moments — the giggly getting ready in the toilets at 7pm and the vomiting in the gutter at 2am. No one remembers the bit in between anyway.

If your party has been cancelled don’t be sad. Just try to think of it not as a personal deficit, but as a shiny Christmas bonus.

Times Recommends

• Unite workers! You’re in Mr Brown’s pocket
• Obama is bashing on the brick wall of unlogic
• Want to understand the war? Ask the generals