The Nix: Story of Asylus Crux, Book I.

Eira lives in a nomadic village, called the Western Tribe. Centuries ago, the world fell into famine and environmental disorder. 15 years from the present, the Western Tribe made a pact with the "Blacklands Emperor" of the north for weaponry to combat the Fae, who built a giant wall to keep the tribe out of fertile territory. Within a decade the Tribe became suspiciously isolated and fascist, and suddenly there are new traditions.

Eira is a rebellious spirit, and is being forced into marriage. However, she's in the center of a multiversal stage, and her freedom depends on an offer. That is, of course, the invisible dragon proposing it isn't a figment of her imagination.

This is the prologue to an epic involving the quest to end the Reign of Dracas, an immortal and god-like conqueror wrecking chaos and misery through the universe. It taps on the concept of spirituality, physics, and human nature. It has sword fights and space ships if the latter doesn't do much for you.