A Radical Affair - Darnalay Castle Series, #3

What harm could one night of pleasure do?  Cybil Bythesea is imprisoned in a marriage that ended ten years ago. That's when she fled the cruelty of her husband, Lord Falstone, and took refuge at her father's estate in Northumberland. Since then, her family's money has kept the villain at bay, and she's been able to pursue her creative passion-writing. But freedom, true freedom, has been beyond her grasp.  Except for her clandestine liaisons with Will.  Will Chisolm is haunted by the past, the tragedy of his family's eviction from their ancestral Highland farm, then his own foolish descent into political radicalism.
Even now that he's gained wealth and respectability as the manager of a set of spinning mills in Glasgow, he's burdened with more responsibility and guilt than anyone knows.  But there's something about Cybil-a lightness, a kinship that, at least temporarily, makes all Will's troubles fade away. It's a dangerous game. Cybil is his employer's sister, the wife of his political enemy and for the last four years, his lover.  She's also with child.
Will's child. And their world, their lives, will never be the same.