Traitor in My Arms — Vivian Lord

From back cover: BRAZEN BEAUTY. She was a hellion with dark burning eyes and fiery hair, and Stephen Raike was determined to have her. But he had not reckoned with the hate Dona Olwen had nurtured since childhood against the Raikes, the hate that had fired the Comanche blood in her and driven her to become an outlaw...hate that would make her the wife of the powerful, handsome man she reviled...and a captive of her own wild and reckless heart!