I have written about happiness, how it can strike anywhere at random times - like in the sauce aisle at the supermarket.
When it does make an unexpected appearance, I'm learning to ride the flow, surf the wave, grab the daisy. Who knows how long it might be until that sneaky feeling reappears?
In the past couple of weeks I have seen extended family members going through hard times.
They've been caught in the rip, dumped by the wave and squashed the daisy.
The flipside of happiness - and apparently just as natural - is sadness.
I'm not talking about clinical depression here.
People trapped in that quagmire are facing a whole different world of pain.
But all of us know about sadness.
One of my friends is facing a grief she can't even talk to her partner about - because it involves a problem with his health - another is going through a very public trauma.
Both bring with them a crippling sadness that ripples out to all their family members.
I'm no expert in this matter, but I do know what it is to be sad.
To listen to someone you love sob quietly in a room next door to their partner is gut-wrenchingly sad.
To hear about the trials of someone who has done their very best to right their past wrongs and still fallen down is achingly sad.
Sometimes I feel getting up in the morning is sad. Sometimes we just are sad, with no rhyme or reason as to why.
When I fall into the world of sad, I think I will never climb back out again.
I think this is the way it's going to be forever, so I might as well eat the whole pack of Tim-Tams, drink a bigger glass of wine, stay in my pyjamas.
It's not the case.
It's never the case.
It's still nice to stay in your pyjamas, but for some reason, the sun is suddenly out again and the sky is blue.
That's simplistic, I know.
It doesn't fix the health issues, the legal issues, the money issues, the endless issues that we all face.
But maybe we can just understand.
Maybe we can just be there to listen to someone sob, to not judge them when they fall.
Maybe when someone says they just can't do something today, they're just not up to it, we can accept it.
Because we all get sad. And it's okay.
It's just as natural as being happy.
Marie Low is a freelance journalist