The Lunar Curse by C.J. Pinard

As Ayla continues to hone her craft of fighting and perfecting the use of weapons with the help of her mentors, Evan and Karina, she continues searching for both the vampire who turned her into the hybrid she’s become, and head vampire Linden, the one responsible for ripping her family apart. Once she locates her assailant, she comes to realize he may not be as easy to kill as she thought, but is in no way giving up. She tirelessly stalks him, which leaves her little time for much else—including a love life.

Unfortunately, though, neither Ryder nor Kellan are willing to give her up. But Ayla has no time for relationships, as she has a much bigger agenda: Finding Linden and ending him. Through a vision, she finds out not only that Kellan is betraying her, but might just be the one to lead her right to Linden.