The Rules of Marriage — Sheila Bishop

Lady Charlotte Rivers was young and inexperienced when Kit, Lord Brancaster, asked for her hand in marriage. However, his fierce good looks and strong mind quickly won her over. And once they were married, the passion that flowed between them was deep and fulfilling.

But Kit's work as a member of Parliament and his charitable crusades took him away from home more and more. Charlotte soon discovered that his best friend Gerard was a handsome and charming escort.

Suddenly Charlotte found herself involved with Gerard. It seemed harmless enough. After all, many respectable women had affairs. Even Charlotte's mother.

But when Kit found out, Charlotte discovered she had a lot to learn about...The Rules of Marriage
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CORGI UK Edition

The Hon. Charlotte Rivers was only seventeen when her childhood hero Kit, Marquis of Brancaster, declared his love for her. After a rapturous honeymoon in Italy, followed by the birth of an heir, the bright and spirited young woman took her place in London Society and revelled in the gaiety and glitter of her carefree existence.

But her happiness was marred by Kit's frequent absence. Sheltered from the unpleasant all her life Charlotte failed to understand why Kit's duties as a member of the House of Lords, and a champion of the poor, must involve him in long hours of hard work. She stubbornly refused to give up her pleasures and accepted the solicitous Gerard Winton as her escort. Charlotte had long been accustomed to seeing her mother and cousin conducting discreet affairs but she was too young to understand the unwritten rules of marriage. Too late she realised that loving should always be important...