Fyfa’s Sacrifice by Jayne Castel

Few secrets can be kept forever. She married him for her cause—but her real identity puts them both at risk. Sacrifices and second chances in Medieval Scotland.
Fyfa is tired of keeping secrets from her husband. However, her marriage to the steward of Stirling Castle is based on a lie. Belonging to an order of druidesses sworn to protect Scotland from invaders, Fyfa’s dedicated her life to preserving Scottish freedom. She wed him in order to gain access to those who rule Scotland—and now, five years later, she’s locked in a marriage to a man who distrusts her.
Hume Comyn thought he knew his wife—but with each passing year, he realizes he does not. Fyfa’s mysterious ways lead him to believe she has taken a lover. He has no idea who she really is.
Estranged and distrustful of each other, Fyfa and Hume are locked together in Stirling Castle as the English lay siege. But after Edward of England unleashes a new weapon that spells Scottish defeat, husband and wife must work together to help protect the man who will save Scotland.
But can they also rescue the ruins of their marriage?