Beasts of the Heart by Blake Hollister

Tala Lovac thought she was done fighting. After half a decade staining the desert sands crimson, Tala had finally come home. Despite her desire to separate herself from the demons of her past, they come back to haunt her with a vengeance. Determined to protect what family she has left, she flees from the city as soldiers storm the streets.

When death comes for one of her own, she can no longer keep the impending war at bay. Tala has a choice to make. Will she fight back against the people who trained her? Against the army she once served.

It's not just her life on the line this time, it's everyone she cares about.