I really believe that all of us have a lot of darkness in our souls. Anger rage fear sadness. I don't think that's only reserved for people who have horrible upbringings. I think it really exists and is part of the human condition. I think in the course of your life you figure out ways to deal with that.
Don't get me wrong magic is cool. But a nervous mother singing to her child at night while something moves quietly through the dark outside her house? That's a story. Handled properly it's more dramatic than any apocalypse or goblin army could ever be.