You read all the papers as a matter of course if you do this job – the good, the bad and the ugly.

Occasionally there are headlines that make me feel so nauseous and distressed that I can’t make myself read the accompanying articles, even though I know that telling my editor I haven’t - can’t - read certain stories, let alone write about them, makes me sound feeble in the extreme.

There was one recently about some depraved women who had made their babies fight each other; even though I avoided reading any of the actual coverage and put my fingers in my ears when the case was reported on the news, the headlines were such that the story kept popping into my head and making me feel sick.

It happened again on Friday night, when we were at a friend’s house and a copy of a London evening paper was lying about. There was an adorable blonde toddler on the front page; the headline included the words “missing” and “kidnap”.

I felt a great wave of nausea and a sort of blind empathic terror and pushed the paper away. It didn’t do any good – I lay in bed some hours later thinking about the story and unable to sleep.

Ridiculously, I went and fished my three-year-old daughter out of her bed and brought her down to mine at about 1am, prodding the poor child awake to tell her how much I love her.

Now I have made myself read the coverage of the abduction of Madeleine McCann, aged three, from her bed at an upmarket holiday resort in the Algarve. I have watched unbearable footage of her distraught parents, Gerry and Kate, both 39-year-old doctors from Leicester, appealing for her return. I know that Madeleine and her siblings, two-year-old twins Amelie and Sean, were longed-for children that were born as a result of IVF.

The line that is sticking in my head comes from a newspaper report that quotes Mr McCann’s sister, Trish Cameron, describing the phone call she received from her brother. “He was hysterical and crying his eyes out,” she said.

Describing what had happened – the couple were having supper 200 yards away from their accommodation, where they had left their three sleeping children, whom they checked on every half an hour – Ms Cameron said: “Katie came screaming back to the group crying ‘They’ve taken her, they’ve taken her’. Gerry was crying and roaring like a bull.” It’s her description of that roar of pain that sends shivers down my spine and will lodge itself in my head for several weeks to come.

The resort the McCanns went to belongs to the Mark Warner holiday group, which specialises in providing family-friendly holidays to the middle classes. You know the kind of thing - children’s clubs, crèches staffed by trained nannies, swimming pools heaving with toddlers, smiling, sun-baked parents rolling their eyes at each other over their children’s little misdemeanours.

Part of the appeal of such holidays is the feeling of safety they engender. You get to whatever resort you’ve booked and are pleased to discover it populated by recognisable types - cheerful family groups, all of them enjoying holidaying with their children, none of them the kind of people who wallop their weeping kids in Sainsbury’s. You heave a sigh of relief. “Everyone is like us,” you think. “Nothing bad could happen here.”

So you let your children roam, you relax in the sunshine, you think that when they’re asleep you’ll just head on over to the bar and have some tapas and do exactly what the McCanns did - check on them every now and then. I’ve never done this myself with such small children - I’m too paranoid about choking and suchlike - but more or less everyone else I know has: the feeling of safety such holidays engender make it not just easy but perfectly reasonable-sounding. Which it is: sleeping children, locked door, benign environment - what could possibly go wrong?

And what couple, preparing for a holiday, hasn’t had the conversation about how old children need to be before you can leave them sleeping for a couple of hours? It’s a parental rite of passage: we’ve all done it. We all need to do it: haring around after small children in the heat all day deserves a couple of hours of wind-down adult time by the evening.

As I write, the Portuguese police have confirmed that Madeleine has been abducted; they also say they believe she is alive and somewhere within a three-mile radius. While this is relatively cheering to know, it does nothing to alleviate the feeling of horror.

We can imagine, without any effort at all, what a beloved three-year-old must be going through, snatched in the night, taken God knows where, for God knows what purpose. That’s another thing: your thoughts don’t stay still with this kind of scenario, they get darker and darker as the hours tick by.

You feel that awful impotent anger and start reexamining your views on capital punishment. And all the time there is that low-level nausea fighting with the urge to leave News 24 on in the background, just in case something good happens.

Keeping hold of your sanity as a parent depends on believing that the world is fundamentally benign. We all know that there exist mad people whose pleasure it is to harm children, but we also like to believe that they are not in our orbit. We spend a lifetime creating safe, happy environments for our children and keeping badness at bay.

The reason why Madeleine’s abduction is so distressing - more distressing, I am ashamed to say, than the tens of thousands of incredibly distressing things that happen globally on an hourly basis - is the sudden collision of the safe world with the terrifying, dark, malign version.

We can give money to the latest appeal for Darfur and we can be angered and appalled by the situation there and in half the world, but the badness and the pain are not part of our recognisable world. Suffering on an enormous scale is shocking and terrible, but not as instantly recognisable as the suffering of a family just like ours, of a child like the one having her afternoon nap upstairs as I type.

I used to feel bad about this, believing it to be a monstrous kind of egocentrism and a spectacular failure of imagination, but I don’t any more. It comforts me to know that this morning, millions of people will be praying, in whatever way, for the McCanns and for Madeleine’s safe return.

Perhaps that is clutching at straws. I hope with all my heart that it isn’t.