Deepest, Darkest...

Deep can be either good or bad: deep feelings, deep blue eyes, deep rich baritone, or deep guilt or a deep sink hole. Dark seems to be a bit more negative generally: dark mood, a dark pit, dark as the inside of a goat's stomach, dark wilderness; but dark can also be positive: lost in the desert they longed for the approaching cool of darkness, rich and smooth as dark velvet, dark chocolate (my favorite). However when the superlative form of both words occur together, most of the familiar completion responses are negative, or at least, suggestively ominous.
Deepest, Darkest.... :(most popular responses--in alphabetical order) Africa, fears, forest, secrets.

Overwhelmed by the oppressive darkness,
She suddered with silent sobs,
Pushing away the shadows and her fears.
Isolated by guilt, she struggled with the knowledge
of her sin and of its unforseen ramifications.
Never could she have suspected the involvement
of her sister, her sweet baby sister;
Never have guessed the impact on her best friend.
Now it had all exploded.
Everyone was hurt and no one trusted anyone.
But only she knew it was all her fault.

In that guilty knowledge
Was the deepest darkness
And the sharpest pain.

Would it all finally heal over for the rest
If she kept this bitter secret to herself?
As she bore the guilt, could she also bear the pain?
Oh, what a deep dark pit or cave
She felt herself entrapped in.