What emotion?

The emotion I feel oh so often,

It’s so loud, always shouting in my ear.

It’s so rough, like sandpaper on my skin.

It’s so confusing, going every which way at once.

It’s so complicated, having thousands of intricate threads and pieces woven together.

It’s so quiet, whispering the darkest secrets of the world to me.

It’s so hard, both to swallow and to feel.

It’s so predictable, I always know what’s going to happen when I feel it.

It’s so simple, since In the end it’s only thoughts.

I wish I never had to feel it, and I only wish the feeling on the worst of people.

What emotion is it?