Lady Saves the Duke by Annabelle Anders

The duke must decide. Should he make this mouse a respectable offer? She’s harmless, really. Marrying her shouldn’t upend his life… His heart, however, is another matter…
Miss Abigail Wright, disillusioned spinster, hides her secret pain behind encouraging smiles and optimistic laughter. Self-pity, she believes, is for the truly wretched. So when her mother insists she attend a house party–uninvited–she determines to simply make the best of it…until an unfortunate wardrobe malfunction.

Alex Cross, the “Duke of Ice,” has more than earned the nickname given him by the ton. He’s given up on happiness but will not reject sensual pleasure. After all, a man has needs.
The week ought to have been pleasantly uneventful for both of them, with nature walks, parlor games, and afternoon teas on the terrace…but for some inferior stitchery on poor Abigail’s bodice.

And now the duke is faced with a choice. Should he make this mouse a respectable offer and then abandon her to his country estate? She’s rather pathetic and harmless, really. Oughtn’t to upset his life whatsoever. His heart, however, is another matter…