My daughter is flying the nest - is it OK to be thrilled?

My eldest girl is in the middle of setting up her first home - she's getting a place with her long-term boyfriend. Suddenly life is a blur of checklists and domestic appliance reviews. I'm trying desperately not to interfere, but it's all so exciting.

My friend is appalled by my enthusiastic anticipation of the now imminent day when Bronte, 22, and her fella will be handed that oh-so-special first set of keys.

It will be a seminal moment in their lives - and also my own. It will mark the day when I become the mother of a woman who is living a truly independent life.

But, according to my pal, while they're allowed to get as excited as they like about this turn of events, as a parent I most certainly am not.

"Poor Bronte," she chides. "You're so eager about it all, she'll think you're glad to be rid of her."

Nothing could be further from the truth. Bronte was my first baby. She is the child who made me a mother and of course I feel a pang at the knowledge that she's about to take her fledgling flight from the family nest.

But the emotions overriding the inevitable sadness that we'll no longer be living together are deep pride and a strong sense of parental satisfaction. I've raised a woman able to stand on her own two feet - it doesn't get much better than that.

Nostalgia is a feature, too, as her move prompts enjoyable conversations between her father and I, taking us back to the time we bought our first home together at a similar age.

It also helps that we're fond of her partner. We know it won't be easy for them - money will be tight and domestic responsibilities on top of their full-time jobs will be a burden. But I'm still struggling to find any great negatives.

So, is my friend right in finding my cheerful approach unnatural? Or is it in fact OK to feel OK about an empty, or in our case, with two more daughters still under our roof, emptying nest?

"It's absolutely OK," exclaims Dr David Holmes, senior psychologist at Manchester Metropolitan University. "Getting your children to the point where they can fly the nest is the entire purpose of parenting.

Whether I'm quite so chirpy when our youngest girl, now 11, waves goodbye, remains to be seen

"It can't be emphasised enough, in evolutionary terms, that when your child moves out it signifies that you've achieved exactly what nature demanded of you.

"Your overriding feeling really ought to be one of achievement, because this moment signifies a job well done. Nature wants us to cheerfully launch our children out into the wider world - it doesn't want us to mollycoddle them into middle age, never feeling quite able to let them go."

The fact that my daughter is even in a position to leave home, under her own steam and at a time when so many of her peer group find it easier to stick with their parents, feels like something to celebrate rather than sulk about.

Especially when figures from the Office of National Statistics have one in four people in their 20s and early 30s - 3.3 million - still living with their parents. That's 38 per cent more young adults deprived of their independence than there were in 2003.

There are many factors at play here: increasing house prices; the escalating cost of living; people choosing to stay in education or training for longer and deciding to marry and start families later. No doubt the fact that living at home is often the more attractive lifestyle option plays a part.

But while I'm reassured by Dr Holmes' words of encouragement as far as my response to Bronte moving out is concerned, I'm equally wary of feeling too smug. The fact I still have two children living at home almost certainly softens the emotional blow.

Whether I'm quite so chirpy when our youngest girl, now 11, waves goodbye, remains to be seen. It's certainly upsetting to see my reproachful friend struggling to come to terms with her own now completely empty nest.

Her 23-year-old son - the younger of her two children - moved out a couple of months ago. Now she and her partner rattle alone around what was once a bustling family home.

She says the whole mood within the house has changed - it's too quiet and despite years of complaining about constant domestic chaos, she suddenly finds herself experiencing a sudden lack of purpose. It does sound awful.

Jo Hemmings, a behavioural psychologist, suggests that much of the problem here is rooted in the fact that my friend turned a blind eye to what was coming.

"It sounds harsh," says Hemmings, "but empty-nest syndrome is based on parental insecurity, and a fairly determined effort to remain in denial of the fact this day was ever coming in the first place.

"If your kids moving out leaves you bereft, then you have an unhealthy dependence on them for your happiness and sense of purpose, which is something you ought really to address long before they get the packing boxes out."

She suggests focusing on the positives connected to this life stage - this is a chance for you, as a parent, to focus on yourself rather than your offspring. By developing hobbies and interests that have nothing to do with your children while they're still living at home, you'll nurture a sense of self that isn't remotely dependent on your role as a parent.

HOW TO COPE WHEN YOUR CHILD MOVES OUT

And of course, it's not just your own feelings that are impacted upon by your child moving out and forward in life. This represents an enormous emotional upheaval for them, too.

We all learnt that Bronte and her boyfriend had got their house while she was still at work. She returned home to find her parents and two sisters arguing over who would inherit her bedroom and what we each planned to do with it. This didn't go down well.

"Some parents keep the departed child's bedroom as a shrine, ever hopeful they'll return home to it, which is unhealthy," says Hemmings. "But getting the paintbrushes out while their bed is still warm isn't a good idea.

"Leave a decent period - at least a few weeks - after your child has left before you start turning their childhood room into your new office or dressing room. You don't want them to leave feeling you've had designs on it all along.

"But do move forward and claim that space and do something good with it. It will help you feel more positive."