Dusk’s Portent by T.A. White

Sin city just got a whole lot bloodier

Fae trespassing in her woods is the least of Aileen’s problems when her best friend comes under magical attack on the same night. Aileen soon finds herself neck deep in trouble as news reaches her that the local Fae burrow has fallen and the werewolf pack she counts as ally has been taken hostage.
To save them, Aileen will be forced to travel across country to Las Vegas, the territory of a dangerous supernatural. And home to the secrets of one close to her. Soon, she’ll find her enemies have joined hands. Their goal—the death of Aileen and the entire vampire line she belongs to.
With the pack’s fate—and her own—in jeopardy, Aileen will need to seek out the darkness inside if she has any hope of surviving until dusk.

This time—what happens in Vegas may actually kill her.