A Crown of Star & Ash by Victoria K. Taylor

When the kingdom of Praiton began overthrowing the surrounding kingdoms of Krigor, no one knew why.

As a healer for Praiton, Deya believed that there was no higher honor in the realm. But when Deya is imprisoned after learning an enormous secret that threatens the regime, her love and loyalty for her kingdom is shattered. Beaten, and tortured, a new, terrible power is unleashed inside of her, a power that she cannot control.
Forced outside of the only kingdom that she has ever known, Deya has no choice but to team up with a band of unlikely rebels that all have one thing in common: the desire for the destruction of Praiton.
One of those rebels is Caelum, a male who spent most of his life inside a prison. Having lost everything to Praiton, Caelum hates everything and everyone from the kingdom…Including Deya. But Caelum has a secret, one that could turn the tide of the war, and one that keeps him pushing everyone and everything away.

As Deya struggles to recover from the trauma of her imprisonment, she is forced to face where her allegiance lies: with the kingdom that betrayed her, or with the male who could destroy it forever.