How does Mark Fossie evolve from the beginning of the chapter, "The Sweetheart of Song Tra Bong", to the end of the chapter?

I think Mark initially thought he had a good thing going by ordering a fiancé, but his reality did not meet up with his expectations. Mark's fantasy dis not account for the fact that Mary Anne was a real person and not subject to male fantasy. Mary Ann eventually goes into the mountains to fight. Mark certainly suffers emotionally for his dashed expectations but I'm not sure we know enough to call him a dynamic character.