Her Heart's Desire — Anne Holman

Viscount John Coombe is forbidden by his war disabled father to fight Napoleon, and is told to marry. Soon after John meets Felicity, her maid steals her precious necklace and takes it abroad. John grasps the opportunity to go and search for it, taking Felicity and her aunts so that no one will suspect he is on government business. Felicity begins to wonder if John really loves her. Was his offer of marriage a mere convenience?