Power of positive thinking

Why do we sometimes feel
Like being miserable
When there is nothing
Absolutely nothing
To be miserable about?
The sun is shining
All is good
But wayward thoughts
Go off on a journey of their own
Hunting for something to be miserable about
Like a cat
Bringing home a dead mouse
It’s not what I wanted
But I’m stopped from what I was doing
I have to deal with it
Try and get rid of something unpleasant
And how much too easily
We become absorbed in the unpleasantness
How to get rid of it?
That’s what I asked
And back came an answer
See it here
Perhaps we can’t stop the cat from hunting
But we don’t have to play with its dead mouse
Analyse over and over
Just bury it fast
And move on.