Lord of Secrets by Mary Gillgannon

An enigmatic Welsh wise woman. A bold English knight. The first time they are alone, she draws a knife on him. From there, things get interesting.

William Fitzhugh is proud to be named lord of Higham Castle on the Welsh border. But defending and managing the castle and the lands surrounding it is a huge responsibility. He needs a wife to aid him, but the only woman who interests him is the local healer, Rhosyn, a mysterious Welshwoman who wants nothing to do with him.
Rhosyn fled the traumatic events of her life in Wales to begin a new life at Higham. She hopes to earn the trust of the local people and become accepted in the community, and she fears the new lord of Higham will ruin her plans. The English noblemen she’s known previously were arrogant and cruel. She doesn’t expect this giant of a knight be any different.
From the beginning, Lord Fitzhugh confounds her. He seems to genuinely want to do right by the people of Higham and make certain they prosper. Rhosyn is surprised and intrigued by the handsome young lord’s generous and reasonable nature. Other people see it as a weakness and scheme to bring him down.
William is entranced by the lovely young healer and admires her knowledge and dedication. But she remains wary and elusive. As the passion between them builds, so does the weight of the secrets keeping them apart. Secrets that have the power to sever the fragile bond between them and destroy all they care about.