The Gods of Men Tome 1 (Broché)

Magic is forbidden throughout the Five Provinces ; those born with it are hunted and killed. Sable doesn't know her music holds power over souls—not until, at age nine, she plays her flute before the desert court and accidentally stops her baby sister's heart. Horrified by what she's done and fearing for her life, she flees north, out of Provincial jurisdiction and into the frigid land of exiles and thieves, known as The Wilds.
There. Sable lives in hiding and survives as a healer. But now, ten years later, someone—or something—is hunting her. On the run again, Sable's best chance for survival is Jos, a lethal man from the Five Provinces, who claims to need her skills as a healer to save his dying father, and she needs the large suns of money he's offered. There's something about him Sable doesn't trust, but she doesn't have many options.
A spirit of the dead is hunting her, summoned by a mysterious necromancer, and it's getting closer. Sable soon discovers she's just the start of the necromancer's plan to take over the Five Provinces, and she's the only one with the power to stop it. But harnessing her forbidden power means revealing it to the world, and the dangerous Provincial, Jos, she's beginning to fall for.