Sons of Sigurd Series by Jenni Fletcher

He’s sworn celibacy… Until he gets vengeance! Danr Sigurdsson is indebted to the captivating, mysterious healer living alone in the wilderness who carefully tends his wounds. Consumed with anguish over the massacre that killed his family, Danr has sworn not to touch another woman until he finds those responsible. So resisting Sissa should be easy, but as they search for the truth, fighting their mutual attraction becomes the hardest battle…