My Sweet Folly — Laura Kinsale

His letters began with "My sweet Folly..." Over seven years, the innocent correspondence between Folie Hamilton and her husband's cousin in India, Lieutenant Robert Cambourne, transformed into a secret passion. After Folie's husband died, Robert became the guardian of her stepdaughter, and, on his return to England, summoned them to his imposing estate.

In an instant, Folie's expectations of a heroic soldier were destroyed. For this Robert Cambourne was a man on the edge of madness, tormented by unseen demons. Possessing a dark seductiveness and a tempestuous nature, he both frightened and fascinated Folie. But fear turned into desire and madness into mystery as Folie was drawn deeper and deeper into the danger that surrounded him...