Here's a scenario:
You get that well known feeling of wanting to cry. Like your body and mind needs it for some reason.
I'm not an expert, but crying should have some sort of purpose. Some sort of underlying biological explanation. Something which makes it more than just a sign of being wimpy.
Anyway, you get that feeling....
But you can't do anything with it. You're stuck. You suddenly remember that this happens all the time. That you can't cry. You've lost the ability to cry.
///twenty and dry