The Runaway Bride by Lynn Kerstan

Colonel John Corbett, on the way to London for his wedding, spots his fiancé in a public coach headed the opposite direction. To prove his love, John decides to play Knight Errant to the romantical Penelope Wright. But everything goes awry, and as he launches himself on a quest to track her down and win her heart, he could well be dubbed “Sir Lostalot,” with “errant” the operative word.