Yesterday I passed a woman wearing a “Bored of the Beckhams” T-shirt. Rather passé, I thought, considering they’ve fled Britain to weary a whole new continent. The slogan that many people would choose to wear, although at least for the moment some residue of decency prevents it, is “Exhausted by the McCanns”.

I am not being glib here. This week, in common, I’d guess, with many of you, I have been agog at how easily sympathy can metastasise into accusation, how the qualities first admired in the McCanns – fortitude, respectability, religious faith – can be reappraised as emotional frigidity, bourgeois arrogance, weirdness.

How quickly a crowd’s cheers turn to boos. Found guilty then, without a trial, even though in order to conceal, then move, then move again a by-then suppurating corpse, leaving barely a trace, while tracked by the world’s media, the McCanns would surely need to be both poker-faced psychos and possessed of magical powers.

So why do newspaper mailbags and a legion of internet forums brim with bile? Why have 17,000 people signed an online petition calling for social services to remove the McCann twins? Why this sudden outburst of dark jokes in Private Eye and internet quips about how many children can be carried in a new vehicle called the “Renault McCann”? Is it really fury at what Kate and Gerry McCann might have done? Or is it that the possibility of their guilt has given many permission to vent, at last, emotions they have bottled up all summer long?

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BACKGROUND

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• The forgotten victim in the McCann case

Multimedia

• Pictures: searching for Madeleine

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Until this week, the only anti-McCann public expression was in early July when parents complained to the Advertising Standards Authority about a Find Madeleine campaign film screened before the start of Shrek the Third. How dare the McCanns scare our children, they protested, when we have strived to protect them from this terrifying story? But what they also felt, but could not voice, was: stop scaring us, stop ratcheting up our already thrombotic levels of parental paranoia, so we cannot even snuggle up with our toddlers during a Urated cartoon without the intrusion of your horror and grief.

Madeleine sucked the carefree out of summer. If a child could be snatched from a blandly safe Mark Warner resort bedroom, clearly parents must now maintain the highest state of alert. Paedophile rings were stealing babies; but with only the vaguest information about their methods or likely power, it felt as if some older, primitive, unfathomable evil was at large.

Parents re-evaluated risk, canned dinners à deux or that late-night sneak down to the hotel bar for fear not just of loss, but of the purse-lipped fingerpointing of the self-appointed child police. Our already overconstrained kids were kept ever tighter at heel. Hysteria was almost tangible. When a friend mislaid her seven-year-old at the Hay-on-Wye literary festival, security guards at once barged aside bookish middle-aged folk and the building was put into “lock down”. (The child was browsing in the book shop.) But living in a perpetual Code Red makes you anxious, weary, resentful.

And there was no escape from that icon of parental inattention, Madeleine’s trusting face. No media campaign has ever been so overwhelming. What parents of a lost child, particularly a professional, well-connected couple such as the McCanns, would not project her face on to every website, windscreen, digital TV channel? And in order to master the media hydra, why not hire consultants and PRs? Why not hire new ones, as the McCanns did this week, use lobbying and spin and strategy, the war chest of the modern age? Why should Mr McCann not update his daily blog even as his heart breaks or address the Edinburgh TV Festival if doing so makes him feel he’s doing something, when there is really nothing left to do?

It is just this slick professionalism feels incongruous with the rawness of loss. And sometimes, as with the cinema announcement, it appeared the PRs had fallen into default mode: as if the object was to market Brand Madeleine rather than to find a little girl. After all, why harangue Shrek-going parents? No group on earth is more likely to be aware of and sympathetic to your cause. It was hard not feel manipulated, to wonder – then hate yourself for wondering – if Mrs McCann was twisting Cuddle Cat in her fingers for comfort or because she’d been told it would play well on TV.

All summer we have listened politely, tried not to think too deeply about the McCanns’ pain, not squirm at their ill-advised, too-private photo-ops – kissing their twin babies goodbye to meet the Pope – but no, in the end, we haven’t seen Madeleine, we’re sorry, we don’t know where she is. And our impotence, our strained sympathy, a sense of being pestered as if waylaid by a charity “chugger”, has darkened our mood, until we want to say – but cannot – please, please go away.

And in allowing themselves to be creatures of the media, the McCanns have become the Beckhams of grief, prey to the celebrity culture that trivialises all in its wake. Among their positive facets now being used against them are the McCanns’ good looks. A plainer couple would have received sufficient coverage, not this cult-like overexposure. In June I heard senior news executives joke about how much they fancied Kate McCann, even more hotly now that worry had unveiled her amazing bone-structure. A magazine editor said she was restraining herself from running a spread on Mrs McCann’s seemingly infinite supply of summer tops: her heartbreak wardrobe. And news on Thursday that her diary had been seized by police immediately provoked publishers to prepare for a bidding war.

But then their celebrity may be all they have left, now that even their profession is being used to damn them. At first being doctors was evidence of the McCanns’ irreproachable characters. Now it is twisted to suggest they would be insouciant about death, blasé about medicating their own children.

And perhaps in the end, we need the McCanns to be guilty. It is callous to say it, but how can a case that, by necessity, has engaged us so intimately not allow us a stake in its outcome. Given that Madeleine has almost certainly died one way or another, maybe it is easier to accept a parental accident. Yes, let it be a banal domestic: we can guard against that, or so we think. Anything but the cunning, predatory stranger we watch for constantly but can never see.

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