Why? Why? Why? (Major Spoilers)

Why did Francis keep the soldiers waiting who were trying to escape? Why did her lover want to endanger her life, as well as his brother and friends by bringing her along? He could have come back after the war like his brother did. Why would a man betrothed to a woman, come barging into her house in the middle of the night to give her a mirror and tell her he married someone else? Why was she still at the house anyway? Surely she hadn't chosen to marry the businessman over her soldier boy? Oh well, I did enjoy the beautiful English scenery, the handsome soldier, the dresses. As for the uniforms, they looked like garish pajamas.