Waterloo Wedding

This book is related by character to The Six-Month Marriage (the heroes in both books are friends) but both books are standalone stories.
Once childhood friends, Jack and Annabelle are now strangers after she rejected his proposal. When they meet again, Jack begins to suspect that Annabelle's reasons for refusing him were not as straightforward as they seemed. Can they make up for the mistakes of the past and admit their love, as circumstances take them from the glamour of London to the danger of Brussels, which is preparing for the Battle of Waterloo?