The key to feeling good about turning 40, or any age, according to a psychologist.

I recently turned 40 and though this probably means I’m officially too old to be using such terms, it’s had me feeling all the feels. 

From gratitude for making it this far, to excitement about what the next decade will bring, to total and utter confusion about what the hell just happened to the past 20 years of my adulthood.

But there’s something else about turning 40 that can stir up some unexpected emotions. 

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It might be realising, perhaps for the first time, that all going well you’re now at least halfway through your one wild and precious life. Or it could be the fact that your next significant birthday will be 50. 

Let’s just let that sink in for a while...

Or like me, you may have been so preoccupied changing nappies and packing lunch boxes for the past eight and a bit years that you didn’t even notice your youth, much like your career, silently slipping away from you in the process. 

Ouch.

Potentially even, when you were younger, you had a vision of yourself in midlife as a proper, grown-up person. 

Someone who understood things like franking credits and the Dow Jones and knew how to fold a fitted sheet. And then one day you wake up and find yourself officially 40 and still confused by most aspects of tax, yet completely across the #FreeBritney movement and not quite feeling as adult as you possibly should. (Confession: also me.)

Then there’s all the talk of life beginning at 40, like we’re finally getting to the 'good part'. I can’t help but think this puts a lot of pressure on our 40s to deliver something, I’m not quite sure what, but something the previous four decades did not.

There is a well-known quote from Victor Hugo that says, "Forty is the old age of youth; fifty is the youth of old age." And perhaps it’s transitioning into this no-man's-land where you’re not especially young and not especially old that can make 40 such a hard age to acclimatise to.

Whatever the case, it’s made me wonder what is it about 40, middle age or milestone birthdays in general that seems to rattle some of us so much?

In speaking to registered psychologist, Rachael Walden of The Bondi Psychologist, she says a lot of the uncomfortable feelings associated with milestone birthdays like 40 are tied up in our expectations and comparison culture.

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"So more likely what it is about milestone birthdays is people expecting that they've also reached milestones and if they haven't done that, then that can be quite uncomfortable. But there is something about 40 where we think I have to have done X, Y and Z, or my life must look like this," explains Rachael.

"We also do a lot of comparison just naturally as human beings, but especially now we're all on social media. We now have this sort of terribly transparent life where we see everything from lots of people and it leads to lots of comparisons," continues Rachael.

Rachael says hitting middle age can also trip some of us up - often being lumped under the midlife crisis label - because we can feel overwhelmed by a feeling that our life's not our own.

"Rather than a mid-life crisis we can think of it as a crisis of control... that factors beyond our reach are taking our lives off-piste. I would suggest it’s an unconscious moving away from the values that keep you on the track of where you want your life to go and unconsciously you're letting life pull you in a different direction," says Rachael.

"And it might be getting caught up in that 'what is everybody else doing?' kind of mentality or we're on a treadmill to pay for this house, but really why are we doing that? People sometimes don't take stock of that as they're going along and then find themselves in a life that just doesn't feel like their own or not what they really want for themselves," Rachael continues.

"When we wrangle back control of the things that are in our control e.g. how we live our day-to-day lives despite what else is going on, we feel better. This gets us living in alignment with our values and we naturally feel better and our self-esteem increases when we do this," adds Rachael.

And for those of us approaching 40 or any other birthday for that matter, Rachael says the best way to get comfortable with it is to stay close to the things that are most important to you.

"Being value guided in your actions is what's going to make all of it easier. That every year is great, has hard moments, but you get through them pretty well because it's all value-guided behaviour. The more value guided we are, the more our self-esteem goes up, the lower our stress, anxiety, depression - it’s the key to it all. So no matter what age you’re at, if you're very clear about why you're doing what you're doing, it makes it easy. The more you stay intentional in your moment by moment everyday life, the better each age will feel," says Rachael.

And while it remains to be seen, at least for me, if life really does begin at 40, it’s good to know that keeping our values and actions closely aligned can help us feel like we’ve reached the 'good part' at any age.

Emily McGrorey is a writer, digital comms consultant, wife and mother of three based in Newcastle, NSW. You can follow her on Instagram at @emily_mcgrorey.

Feature Image: Getty.