Andre Agassi reinvented his game, personality and haircut over the course of his career

There’s fascinating research that finds by the end of our lives, our personalities change so dramatically that we’re essentially completely different people.

Think about that for a minute.

The Metallica-loving football junky could one day be a mellow bike riding relationship thinker. (Ahem!) And that emotionally defiant tennis headcase can transform into a disciplined conditioning nut.

(Side note: makes you re-think the value of getting tattoos, huh?)

Life is change. If we’re not growing, we’re dying. And most of us choose to grow in wonderful, exciting, and unexpected ways.

But as we grow into You 2.0 and 3.0, the rules change. What used to make us happy–say, blasting Slayer late at night–now mightily annoys us. Traveling the world used to be thrilling; now it’s tiring, and makes us miss our family. Breaking the Wimbledon dress code used to be thrilling, but now seems like a waste of energy.

The thing I find craziest about this is that our friends and family can lock us into You 1.5, when really you’re onto You 3.0 or more. At a recent family retreat I attended, my loved ones said they were really annoyed by some things that Matt 1.2 did. I gotta say, I was ticked off too! Many of my previous versions make me cringe, though I still like the guy. Matt 1.2 seems like a good start with plenty of bugs, an early kludgy version of me (and I still have plenty more bugs to work out).

I’m naturally disposed to be more like a shark, always moving forward, rarely getting stuck in the annoyances of the past. I’m oddly¬†built to quickly accept that there’s just not much point to dwelling; I can’t change it, all I can do is learn and move on. My disposition is a strength and a curse; I move on quickly, but I’ve learned that most people need more time to honor the past and process.

I respect that need. But we also must force ourselves to do the hard work of bending our mental models into adaptation. The easy labels of our college chums fifteen years ago just don’t work anymore when we see them go from frat party lush to nonprofit executive.

One of my favorite columns of all time is David Brooks’s survey on what makes for happy lives. He found that dividing life into chapters, with new eras, adventures and mindsets, is critical to fostering happiness.

And as we change and our partner changes, of course our User Manual must change too.

Do the maintenance. Run the updates. Reassess what you need to be happy and from your partner–not all the time, but now and then. And celebrate the change that’s such an exciting part of our journey.