Madder Mortem riddle wants to be

This ordeal has made you fret,
But you know it's not that bad
We thought ourselves beyond its reach
Well, it seems we've both been had
See, it flows so easily
A ruthless piece of art
And it grows and speaks of mysteries to be
And flips itself to show the deuce of hearts
The riddle wants to be
It rubs our noses in nature's demands
And it wrestles our dearest doubts out of our hands
There is a balance of hope and despair
How we bleed for it!
In our need for it all sense disappears
The riddle wants to be