The Sapphire and the Pearl — Audrey Curling

Lady Harriet Cavendish has always had everything she desired -- except the handsome Lord Granville, whose string of conquests at one time included her aunt, the lady Bessborough, a woman still renowned for her beauty.

When Granville professes his love for Harriet, she can imagine nothing that could mar her happiness -- until she learns of his secret meetings with her aunt and a wealthy heiress, and of his two illegitimate children.

Can Harriet allow herself to trust her love to one so morally irresponsible, so used to the attentions of many women -- and most important, will her heart allow her not to?