The point was drummed into me when my colleagues had a year-end party at my home one evening and turned up with giant numbered balloons.
I knew I had turned the corner on something, but couldn't quite put my finger on it. And it was only when I was reading an article online that everything I had been feeling in recent weeks suddenly crystallised.
It seems that this is the year in my life when I could start to experience a mid-life crisis. Most suggest this could happen anywhere between 45 and 65 years of age.
Wikipedia defines a mid-life crisis as a "transition of identity and self-confidence brought on by events that highlight a person's growing age, inevitable mortality, and possibly shortcomings of accomplishments in life".
This is almost a medical definition of the phenomenon and I find it to be succinct and apt. Yet in real life, we almost never speak about it seriously.
We joke about it, using it as fodder for gossip when someone older we know suddenly buys a flashy car, develops a man-bun or starts taking random afternoons off work for no reason.
Some researchers think this is not even a real psychological condition. They say only a small proportion of adults will ever experience this so-called transition and, even then, the changes weren't necessarily brought about by concerns about ageing.
Whatever the general consensus is doesn't matter.
Like the longsightedness that creeps in millimetre by millimetre more each day as I read my WhatsApp messages, I feel it coming. I've even done all the hokey online quizzes to validate it.
To me, it's an inevitability - especially for those of us that grew up here in the 1980s and started working before the turn of the millennium.
After all, we were a generation that were obediently cleaved to the well-trodden paths in life.
There were courses to study in school that led to stable jobs which paid well - which made you eligible to find a good partner, get married, buy a home and start a family.
We stuck to these life paths even as the world was changing quickly around us and some of us had already begun to suspect this is not necessarily what we valued.
Choices in life also seemed to be opening up at the time. We would hear of so-and-so breaking the mould to do some crazy thing with his life, like a government scholar I knew who left his job after a year to work as a producer at MTV in New York.
But these choices were never celebrated then as they are now and so many of us never had the courage to do what we perhaps truly wanted in life.
Two decades later, most of us are firmly ensconced in the lives we chose.
We have been married or have been in stable long-term relationships with a partner for many years. Some of us have kids or pets and we have commitments to our families. And our daily and weekly schedules have settled into a steady cadence.
We have progressed in a logical fashion in our careers and have important responsibilities at work.
Our bosses and colleagues rely on us to lead teams, based on the not inconsiderable experience we have built up over the years.
But it is exactly at the point when the burden of responsibility feels heaviest that we question ourselves.
You meet a person who inspires you so much with his life story that you wonder what you have done with your own life.
You become suddenly infatuated with someone who awakens a physical desire you thought was long dead and have terrible thoughts about ending your own relationship.
You think about trading all the stress and politics at the office for a simpler job that you find more meaningful or more interesting.
In recent weeks, I've certainly had some of these thoughts. I've also looked at myself in the mirror and asked how many more years I have to look young and attain the image that I want.
It is no help that we live very much in a "FOMO" world, where the Fear Of Missing Out is very real with every Facebook or Instagram photo or video we see of people doing fantastic and ever more enriching things with their lives.
Every self-help bestseller on the bookshelves seems to be about reclaiming authenticity, living simpler or not giving a hoot about what people think.
Our generation lives in a very different world from the one we knew growing up, one where there is much less stigma around course correcting.
The question, of course, is what to do about it.
After all, it only takes a small trigger to set in motion a series of events that could lead to very serious life changes.
There are plenty of stories about people getting divorced and leaving high-flying careers as they navigate the tricky years of mid-life. Some have led to happier people leading happier lives, but others have made costly mistakes they can't turn back the clock on.
A friend recently pointed me in the direction of what's called The Serenity Prayer. Even though I am not religious, recent developments in my life have shown it to be a good guiding principle.
It says that we should ask for the serenity to accept the things that we cannot change, courage to change the things we can and the wisdom to know the difference.
Over the years, my generation has probably regained some of the courage to change the things we can. It is the first and third legs of the prayer which are tricky.
The key is realising, particularly in this current climate of unbridled Ed Sheeran-fuelled, anything-is-possible positivity, that there are outcomes that we cannot have full control over.
Hence there are some things in our lives that we probably cannot and should not change.
That we should perhaps look inward within ourselves for the change needed to weather the crisis, instead of always focusing on the external factors that make up the sum of our lives.
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