The Heart and the Heather (Hearts and the Lands #1)
Nancy Richards-Akers

Pledged to one another since childhood—when eleven-year-old Malcolm Kirkpatrick married the infant Isobel and vowed to safeguard her life—these two spirited hearts were separated through the years.
Malcolm, now a powerful Scots Highland chieftain, is enthralled by the beautiful lady he rescues from a band of thieves. Little does he know it is his wife who quickens his pulse and makes his heart leap. Although Isobel knows she owes her fidelity to a stranger she calls husband, this ruggedly handsome warrior captures her heart as well. And it is in this raging tide of forbidden lust that they discover the intense passion of a true love at long last set free.