Wicked Deeds on a Winters Night by Kresley Cole

Bowen macRieve of the Lykae clan was nearly destroyed when he lost the one woman meant for him. The ruthless warrior grew even colder, never taking another to his bed~until a smoldering encounter with his enemy, Mariketa the Awaited, reawakens his darker desires. When sinister forces unite against her, the Highlander finds himself using all his strength and skill to keep her alive. temporarily stripped of her powers, Mari is forced to take refuge with her sworn adversary. It's rumored that no one can tempt Bowen's hardened heart, but soon passion burns between them, though a future together is impossible, she fears he has no intention of letting her go...