If Ever I Should Love You by Cathy Maxwell

Once upon a time there were three young ladies who, despite their fortunes, had been on the Marriage Mart a bit too long. They were known as the “Spinster Heiresses” . . .
He’s inherited a title, but not a penny to speak of, so the Earl of Rochdale knows he must find a wife—preferably one tolerably pretty and good-tempered, but definitely wealthy, and willing to exchange her fortune for his family name.

His choice: Leonie Charnock, one of the season’s “Spinster Heiresses.” Years before, the earl had saved the dark-eyed beauty’s reputation, and she is still breathtakingly lovely, leading Rochdale to hope that their marriage will be more than in name only.
However, Leonie doesn’t want to be anyone’s wife. Nearly destroyed by the secrets in her past, Leonie agrees to their union with one condition: there will be a wedding but no bedding. But it’s a condition the new Countess Rochdale isn’t sure even she can keep . . .