what the deuce?

"Curiosity killed the cat, ya know."
"Well, good thing I'm not a pussy!"

That's a joke I made up in my head and have never used. It's really not that funny, but I thought of it and laughed, so it merits enough to be mentioned.
I am curious though.
However, I don't know which question to ask myself here,
"Why do I almost always write about sad things?"
or
"Why is it, I only feel like writing when I dwell on sad things?"

I think it all comes down to this: my brain must be wired to be self-destructive, because it always seems to send me plummeting downward in thought whenever I forget enough to be happy. I think I'm meant to be a sadist, but without any pleasure.

Does that happen to everyone, just no one likes to talk about it?
The only times you're happy, are the times when you manage to slip free from the thoughts that always seem to shackle you. Or when there's enough distraction that you don't have time to think.
Maybe it's just me.
Honestly, I hope that's not the human condition. I'd hate to think this is everyone's life.