The Duke, The Wallflower, and the Holly Tree - Christmas Wallflowers, #6

Four years ago, Gabriel Preston, Duke of Beckhampton prepared to ask for the hand of his love, Lady Eliza Clayton. Then she vanished. Rumors ran rampant through Polite Society, each one suggesting a different theory, yet all resulted in the same conclusion: Lady Eliza didn't love him. Vowing never to bare his soul to a woman again, Beck locked himself away on his estate. After protesting, cajoling, and crying daily for four years, Lady Eliza has finally convinced her mother to allow them to return to England from Boston, where they'd been "visiting" family.
She knew the true reason for their voyage, despite Mama's denials. Her parents refused to allow her to marry the Duke of Beckhampton. Yet after all this time apart, Eliza still loved him. Beck is shocked when Eliza appears in Society once more, and even more surprised to discover he desires her after all the pain she caused him. He's feeling the Christmas spirit for the first time in years. Falling under her spell, he plans to profess his love when she vanishes yet again.