There is something worse than a grumpy teenager, my friends and I are discovering. For years we have moaned about the way our young adolescents crash in late at night, keep asking for money, play loud music and never clean up, but now we are discovering that this is infinitely preferable to a spookily tidy, quiet room containing no teenager because the child has flown the nest.
This is the time of year when the silence bites deep. Last year's school graduates are off to university or saving hard before leaving for their gap years. After the last minute flurry of packing and arrangement-checking, suddenly there's no more to do except hope that they make a go of the next stage of their life. And be ready with the washing machine and the fatted calf for their return. My eldest has reached the magic age of 18, and with him all those friends with whom he went to school and playgroup. When they were young, I wasted many a happy hour at the playground chatting about nits and teachers with the other mothers.
Now we are all getting in touch again to compare notes on this new scary stage. We've braced ourselves for this moment, of course. Some people seem to have been psychologically preparing themselves for their children's departure almost from birth, but when it comes, it is still a shock. A great friend who has twins is finding it harder than most. The rest of us have younger children still trailing through the system, keeping us busy with lifts and sleepovers, homework crises and raids on the fridge, but for her the last few weeks have been like falling off the maternal cliff. "I did part of my mourning earlier in the year when first one, then a month later the other, passed their driving tests," she says. "I had got so used to all the chats about their daily lives when I gave them lifts that I hated it when suddenly they were independent. That was bad enough, but it's nothing to the strangeness of speaking to them only on the phone and having uninterrupted dinners with my husband."
As with all things, it is women who make the most noise about empty nest syndrome, but men feel it just as deeply. It took one father I know six months of snapping constantly at his wife and other children to get over his eldest child's departure for university. "I hadn't realised how much I enjoyed helping her with her homework," he told me. "I longed to find out what essays she had been set in university, but I had to restrain myself."
At least, having been so traumatised by that loss, he has found the departure of his two younger children rather easier to bear - and he has learnt to talk about it. Not being open about the trauma of the empty nest can, to put it bluntly, be fatal. There was one woman at our local riding stables who was always one of the eager volunteers to help with everything. She baked cakes, made rotas, threw herself into it, but when her daughter - and only child - moved out, she had no need to drive the horse box any more. Everyone who knew her as this cheerful person was deeply shocked to find that in the week after her daughter left, she drove to the area where she had been born and took an overdose.
It's not unusual for a sense of redundancy to cause severe depression. Missing Persons, a charity which supports families when someone has disappeared, says that the two most common groups to go missing are adolescent men and middle-aged women. Once the children have gone, the latter can feel as if they serve no further purpose, especially if their husbands are caught up in their jobs and the marriage has been distant for some years.
But life isn't over, I and my friends keep telling each other, our voices and faces unnaturally perky from our efforts to look on the bright side. "I'm taking up painting," one said. "Now's the time for me to start learning Arabic," said another. But it's not just our time that we need to fill, it's the need to have people around us. Some are talking of taking lodgers or helping out as mentors for charities.
One friend who is a single parent is planning to move city and start a completely new career now that both her children have left home. Her plight is a reminder to us two-parent families that at least we have each other, even if the sparks of romance are looking a little dim. The women who are coping best are those whose children have gone to boarding school. They have already had years to get used to their feelings of bereavement.
When they waved goodbye to their child, often at an agonisingly early age, they returned home in floods of tears, desperately counting the minutes until they saw their son or daughter again. With prep-school-aged children, there followed a horrible first few weeks when they weren't allowed to speak to them on the phone for fear of stirring up feelings of homesickness, an eternity punctuated only by the bathos of the child's letters home. These were invariably filled only with the kind of impersonal news that had their mothers frantically reading between the lines for signs that the child needed to be rescued immediately.
Of course, most of the children who were sent away to school loved it, or at least became used to early independence. So did their parents, who are now acting as counsellors to those of us who have kept our nests full for as long as we can. "Don't rush to start something new," one said. "Let yourself mourn. It's normal." Another advises booking the kind of romantic weekend a deux with your spouse that hasn't been possible for years, to remind you that you can have fun together, that you amount to more than a child-rearing unit.
As for me, I'm watching my cat. This summer, she offered us the surprise package of five kittens at an age when I didn't even know she had a boyfriend. Despite being a feline teenage mother, she looked after her babies beautifully and I hated the idea of sending them off to new homes because we couldn't possibly accommodate six cats. When the moment came, she didn't seem to mind, which made me think how lucky animals are to be so unsentimental.
Then I noticed for the next few days that she was wandering all over the house, sniffing the drawers, backs of cupboards and other dark, warm places where she had once hidden her kittens for safety, miaowing to them but hearing no response. She was as lost a soul as any of the women I know who sit tearfully in their departed children's empty rooms. But now, three weeks on, with only two of her offspring left, she seems to have completely forgotten about the absentees.
Perhaps that will happen to us human empty nesters, too. And probably, at just about the time when we have got used to our children being grown up and descending only for the odd few days and free meals, they will be back. Then we'll start moaning about boomerang kids.