Time.

Winter arrived. The cold in the air hits your face when you're walking, but it's not unpleasant.
The seasons' changes are welcome: they mark the time flying away, that means you're still living. Often we are afraid for the time passing by, but I'm wondering why. After all, the only alternative of getting old is dying. Not so bad, if you're looking at it from this point of view.
It's a question of perspective, as everything is. We are able to create our happiness or our desperation, it's a decision on which perspective you want to choose.

Happiness is nothing but a decision.