Dangerous Passions by Leigh Anderson

Isoline Beresford has beautiful yet haunting dreams. In them, a man she doesn’t know is calling to her. She’s inexplicably, inexorably drawn to him, until he’s more real to her than her own fiancé.

When she calls off her engagement, her enraged father sends her to live with her ninety-year-old grand-aunt, the Dowager Countess Bellamira Granville. If she won’t do her duty at home, he reasons, perhaps she can at least convince Lady Granville to leave her fortune to Isoline.
But life at Thornrush Manor is not what Isoline expected. Her aunt is as spry and elegant as a woman half her age. Her nearest neighbor, a distant cousin, begins courting her. And a dark and handsome artist proves a pleasant companion.
All the while, her dreams grow more intense. More urgent. More passionate.

More dangerous.
In order to save everyone at Thornrush Manor, Isoline will have to confront the darkest parts of herself-and discover the secret of the man who hides in her dreams.