A Wicked Arrangement — Karolyn Cairns

Gillian St. Armand fled her glittering life in high society London, embittered and disillusioned with her marriage of convenience. Free to pursue her own pleasures now that she's met the terms of their hated arrangement, she is haunted by the lingering desire for the man she cannot forget.
Though Gabriel gave his heart to another years ago, Gillian is determined to bring her husband to heel. Amid the pomp and splendor of Regency England, a lady goes to any lengths to reclaim the man who haunts her dreams, spurring her on a deadly course as intrigue is once more sparked at every turn.
Gabriel St. Armand cursed the day he ever agreed to Gillian's demand for independence, allowing pride and past heartaches dictate his hasty actions. As a deadly plot once more swirls around him and his family, he must conquer Gillian's heart or risk losing her forever. The whims of fate once more conspire against Gabriel, perpetuated by his beautiful and conniving mistress, threatening his bid to reclaim his lovely wife with her heartless ultimatum.
The remaining nobles on the blackmail list have once more turned their eyes to Lord Iverleigh, determined to avenge the past and attain their rightful due. Treachery and betrayal once more threaten Gabriel and Gillian's fragile newfound happiness, forcing them to at last learn to trust the other before all is lost.