Until you own a dog, you are blind to the symptoms of canine distemper exhibited by other dog owners. The emotional rollercoaster, the egregious expense, the foaming at the mouth, the hysterics, the fashion crises, the yapping and the catfights of modern dog culture can easily pass you by.

The madness is much worse in London than in more down-to-earth places. Daily I witness the excess, running with my bedraggled mutt on Hampstead Heath or Golders Hill Park or Primrose Hill. The rest of the pack seem to be wearing cutting-edge yellow or orange fluorescent waterproof safety coats this season, while we are still favouring fur. Dogs with second homes in the country are sporting Barbour-like waxed rain jackets with underbelly protection, while we still dry ourselves by the traditional shaking method.

Dog people all talk to each other in the park, like baby people (but never the twain shall meet). One dog lady told me that while she thought her Yorkie’s army camouflage-patterned coat was “super”, she thought lilac faux-fur coats for dogs were “silly”. “A dog already has fur!” she said. I didn’t say: “And that’s why you didn’t need to waste £12.99 on your Yorkie’s Pac-a-Mac.”

A few days later, I was in the Primrose Hill pet shop and overheard a woman begging and begging for a cancellation in the dog grooming parlour – otherwise she’d have to wait a week for a shampoo and blow-dry, for chrissake. She bared her teeth scarily at the assistant behind the counter. I felt there was some kind of role reversal going on.

Then the mutt and I went for our walk on the hill. Within minutes, one dog friend had introduced us to a dog whisperer with three rescued hairballs following her. The mutt ran away after a boxer friend, in an irresponsible manner. The dog whisperer looked at me severely, her long grey hair waving witchily in the wind, and said: “What on earth have you been feeding your dog?”

Burns organic dried chicken puppy food, I told her, thinking that was rather right-on. “And any chips or squished cakes she picks up on the Finchley Road of course.”

“Oh my God, you must feed her fresh organic mince and vegetables, none of that dried stuff! It is scraped from the floors of abattoirs, my dear! Fresh food, and then her behaviour will improve.” She pressed a photocopied leaflet into my hand, advising on dog food gurus and websites. She wanted to sell me a dog-food advice book for a reduced rate of £15. Then her own dog ran away and got lost, while mine came back when I whistled. I felt unaccountably cheerful.

This is not about the dogs, is it? It’s all about us, and I’m even buying fashionably “organic” dog food that looks curiously like rabbit droppings, and the kids, quarantined last month with the norovirus, set up a website for the mutt on DoggySnaps.com (click on “fetch” to search). You can download your bitch’s bark as a ringtone. In Fulham, you can take your dog for aromatherapy or reflexology, and if you haven’t yet consulted a dog behaviourist, you’re way behind the curve.

This is a whole cultural phenomenon, not just a few pedigree breeders obsessively gussying up their dogs for Crufts. Ever since Paris and Britney (even in troubled times) began using toy-sized dogs as armpit accessories, we knew that the canine was no longer a cheery, independent being, but an extension of all our desires and anxieties. When people started objecting to the words “dog owner”, preferring “guardian” or “companion”, you knew something was rotten in the state of the park.

And here’s a worrying question. How much do you love your dog-companion? How much love can you afford? A friend just paid £480 to have his ancient, bloated Labrador deflated. Another spent close to £1,000 on a Westie with breast cancer – and bitches have many mammaries, so it went on for a gruelling few months. Now that human medicine has left the hospital for the kennel, anything is possible, from chemotherapy to dialysis. “I’m afraid it’s time to put Tiddles to sleep,” is rarely uttered by a London vet with a mortgage.

And what if you die, leaving your faithful companion behind? The Americans are ahead on this one. New Yorker Leona Helmsley left £6 million to maintain her Maltese terrier called Trouble in grand style, and when the dog eventually goes to “the happy hunting grounds” it will be buried with Mrs Helmsley in her mausoleum. Eewww.

You may also enjoy browsing www.palm-meow.com, a cat retirement home in Florida which suggests you set up a “Pet Trust” before you pass away so your cat can “live out his final years” lounging in a diamanté collar by the palm-fringed swimming pool. As you scroll over the images in “a tropical retirement paradise for your cat”, pound signs may light up in your eyes. They did in mine. The Dark Ages Pet Retirement Facility will be opening soon.

kate.muir@thetimes.co.uk

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