The post-Christmas sales have begun, and with them, the startling phenomenon of men making their presence felt in the women’s changing-rooms. This is a disturbing new experience for me, because I am of the generation in which men resolutely refrain from clothes-shopping with their wives and girlfriends, and on the rare occasion when they do – thinking that it is a magnanimous concession – the women wish they hadn’t.

For a woman of my generation, clothes-shopping with a heterosexual man in tow brings back unpleasant memories of trying to do the same thing with a recalcitrant toddler. Shopping for clothes with girlfriends or sisters is a lot more fun – and their input is much more useful. But apparently, that’s not the case with today’s metrosexual generation.

Men in their 20s and early 30s are right there in the changing-rooms, taking an active and participatory interest in the exact positioning of the two-inch zipper on the unbelievably low-slung hipsters that seem to be the sole style in trousers.

Changing-rooms used to be like a kind of harem, with women in various states of disarray, parading in front on the large communal mirror in the corridor between the rows of curtained cubicles, and asking each other – complete strangers – for an opinion (you know the sales girls can’t really be trusted because they want to sell).

Women used to be free to emerge in their underwear so as to hail a sales assistant and ask for a larger size. Curtains would be left half-open, tights and sometimes even knickers would be strewn over the rails, and the atmosphere was very much a “girls’ school” one, without the misery of gym kits and PE. Not any more, I find.

A couple of days ago, I marched into the changing-rooms of one shop that sells clothes only for women and girls, to find at least four boyfriends jamming up the aisle, showing absolutely no sign of embarrassment at being there. They weren’t even waiting just outside, keeping a respectful distance and waiting for a signal from their girlfriend, at which point they would go forward and voice an opinion on sequinned lurex outfit designed to stun them all on New Year’s Eve.

No – they stood instead just outside the curtain, as though on guard, looking around them as though they were on a fairground ride (The Tunnel of Deshabilee). Meanwhile, all the other girls and women whose boyfriends these were not kept their curtains firmly drawn and refrained from emerging unless fully clothed. Some of us did not emerge at all, struggling as best we could to see how the clothes fitted, using just the awkward mirror in the cubicle. It’s no fun at all, turning circles in front of a mirror to see whether you look good or horrendous in something, under the interested gaze of some strange man.

For a brief moment, I thought of marching back out again and asking the sales assistants – who should have been in there themselves, but who appeared to have been squeezed out by the ranks of boyfriends – why men were allowed to saunter into in the women’s changing-rooms, as though they were at a free peep-show.

Then, I thought it would be a lot more useful to write this, and ask the owners of women’s clothes shops to post little signs up against the doorway to the corridor of cubicles: No Men Beyond This Point.

* * *

We call dogs “man’s best friend,” and then somehow fail to credit them with many of the emotions we normally associate with human beings, including intelligent revenge that is the result of observation. Years ago, I had a dog who would pay me back for real or imagined slights by targeting something he cleverly perceived as being closely associated with me: my spectacles, my mobile phone, a book I had been reading, a pair of new shoes I had just brought proudly home.

All of these were chewed up after a difference of opinion that led to a sulk. I think it should go without saying that he was male. My husband used to “pooh-pooh” this perception, by saying that anything I’d handled for a long time – my glasses, my phone, my book – was going to carry my scent and that was how the dog identified them, but this did not explain the malicious delight with which I saw him running round the garden with one of my new and unworn shoes clamped between his jaws.

That hypothesis was finally laid to rest, when one night I despatched him, howling and dragging his claws through the carpet, to his outdoor kennel for the night, despite his having made it clear that he would prefer to carry on lying beside the heater. Fifteen minutes later, I heard urgent scrabbling, followed by a suspicious silence, and looked outside to see my favourite succulents, the ones I had spent most of that day re-potting, lying shredded amid the debris of overturned pots emptied of their soil.

Now, I have spent a good part of the afternoon working on a Christmas wreath for the front door, only to be reminded why we haven’t had one for around 10 Christmases. It is traditional practice for our dogs, after they are put out for the night, to go round the house, banging on various doors and demanding to be let in again, before settling into their kennels.

In their annoyance, they will destroy anything they find on the doorstep, which is why the trunk of the potted tree by the front door is surrounded by an angry ring of fiercely spiked cacti, to fend off such vengeful acts.

This morning, I opened the front door to find the step littered with the wings of glittery Christmas butterflies, and strewn with the fronds of dried artichokes, all of which I had artfully tied to my wreath.

The heads of artificial dahlias, which I thought would make such an interesting change from artificial poinsettia, had had their necks broken, and were hanging at a painful angle.

I have since decided that, if dogs are man’s best friend, then they are friends who should never be crossed at any cost.