Joanna Moorhead: To do this job well, you have to make yourself redundant

I have just dropped my 19-year-old daughter off at university at the start of her second year. My drive home – like the drive home last year, after I'd left her there for the first time – was tinged with sadness. When Rosie's not around, I miss her: and right now, the Christmas holiday seems a very long way off. But the truth is that loving your kids means letting them go: it's what parents do, and it's what we have to do. Not all of us, though, seem to manage it.

Last week saw the case of a couple who have failed monumentally to let their child go. The Italian family, who haven't been named, are from Venice. The parents must be in their sixties or seventies; and their child, a son, is 41. He has a good job, and he earns a decent salary: but he's still living at home. His mother does all his washing and cooking for him, but she can't cope any longer; she's ended up in hospital with exhaustion. Still, though, the son doesn't leave: so, at their wits' end, the parents are now taking legal action to oust their child from their home. He has six days to get out.

It's a desperate solution to a desperate problem: and yet, in truth, these parents only have themselves to blame. They haven't clocked the most basic part of their job description, which is that being a good parent means making yourself redundant. What we all want for our kids is that they grow up to lead happy and fulfilled lives; but in order to make their own choices about how they want to be happy and fulfilled, they have to be independent. And making them independent means weaning them off their dependence on us – even though that may sometimes be painful.

The reality is, of course, that parents – like everyone else – yearn to be wanted, to be needed, to be indispensable. Nothing in life renders you more indispensable than when you're parenting a newborn: everything they have, they have because of you. Without you keeping them fed and clean and safe, they wouldn't survive at all. As they grow up they learn to feed themselves and keep themselves clean and safe – but we parents are still pretty essential, sorting out our children's formal education, paying their bills, and doing their cooking and keeping the house clean.

Sometimes, of course, we complain about how much of our lives our children take up – how much of our time they occupy, how much of our money they cost – but the truth is, at root, that we love it.

We love being so needed; we love being able to give so much, we love being so important in another human being's life. Why would we do it, otherwise? But, wonderful though it is, it can't go on forever; and if we let it go on too long, as these Venetian parents did, we let our children down in the most fundamental way possible. We stop them from spreading their wings, and from finding their own destinies.

So often when you're a parent, the easy thing is to do something, while the hard thing is to do nothing. We're so wired to want our children to do well in life that we forget that genuinely doing well means doing well for themselves, not doing well because we are doing well for them. In the case of the couple from Venice, it was so much easier, for so long, to do their boy's cooking and cleaning and washing for him, rather than forcing him to do his own cooking and cleaning and washing. But the eventual fallout, and it's ugly to see it unravel, is wretched and sad. It's proof, if proof were needed, that when it comes to parenting there's a time when less definitely means more.