The deepest sorrows

Do you know where you can find the deepest sorrows?

It is between the lines, where the words are left unsaid.
It is where you hear silence, in the sea of unnecessary banters.
It is found behind every curve of the lips, trying to give a smile.

It kills never having to wholly feel it, yet you feel it.

Caged. Trying to escape.
But it can't. It won't.