Taran by Hazel Hunter

What if your entire life had been a lie?
When Rowan Thomas was dragged into 14th century Scotland, she knew her old life was gone. But the more she learns of her druid nature, the more she questions what she knew—about her sister, herself, and her all-consuming attraction to Taran Skaraven.
The Skaraven Horse Master has always been a man of few words. He sees to the care and well-being of the clan’s mounts, sensing their needs before they do. But his link with Rowan goes beyond anything he’s ever known. Since their first moment together, they have connected so fiercely that he begins to question his judgment and their uncontrollable need to be together.
As the mad druids and their new accomplice lay final plans for the clan’s end, Taran comes to a stunning realization while Rowan forms a dangerous alliance of her own.