Audacity Gambit

Every teen hits a stretch in life where they feel like they've been forcefully isolated from the world. The standard fantasy trope is that it's all for a reason-they're the Chosen One. They've got to save their village, rescue a princess, find the key.
But 18-year-old Emily's village is a trailer park and the people she's fighting for may have performed more terrible deeds than the enemies she'll have to confront.
With little choice in the matter, Emily plunges head-first on a quest into a fairy world that isn't nearly as fabulous and fantastical as books would lead you to believe, though it's a nice enough place for a vacation.