Why read dark erotica?

This is a question I struggle with, both as an author and reader of dark erotica. It's not exactly fun, the way a light erotic romp would be. Sometimes it can be downright disturbing.

One thing I can say is that I do enjoy a happy ending. By this I mean the hero and heroine must end up together. So maybe that is part of it: I want to know that suffering can end well. I don't think that's the sum of it, though. It's also to explore the dark recesses of my mind. What is going on in there and how do I feel about it? Or maybe I am a masochist through and through. Even in my fiction, I want it to hurt

Recently I received a great review for Trust in Me from Erica at Wicked Reads. In it, she talks about why she likes to read dark erotica:

For me dark erotica holds a very small niche in the erotica genre. When written well it is extremely psychological and fulfills certain needs for the reader. I liken it to a cutter using a razor blade to have a visual release of the pain that is held within their soul.

I love her explanation! It's disturbing (as it should be, probably) but really resonates with me.

What do you think? What drives you to read dark stories?