Secret Fire by Michelle Howard

With a mystery illness plaguing his people, Konlan is in a race against time if he wants to prevent more death and chaos from ravaging his kingdom. When he thinks things can’t get any worse, they do. Enter an old flame that he’s never stopped loving. Breya.
Breya has always known the Goddess of Fate was fickle, but she didn’t know the Goddess could be so cruel. Breya walked away from Konlan and buried her love for him deep within her heart. Now, those old feelings have come roaring back and walking away again isn’t an option. She knows what she has to do to save her race, but how will she save her heart?
With their lives on the line, both Konlan and Breya pledge to do whatever it takes to survive. Even if it means risking their hearts again in the wake of betrayal.