Marriage, romance, and intimacy
Throughout the book, the characters are driven by their youthful passions for each other. When Emily is married to Louis, she can't help but accept the attention of other suitors, which he husband hates. Their relationship models the intimacy issues that can happen when two people don't really trust each other. Emily doesn't understand Louis's jealousy, and their tragic story is surrounded by other various arrangements, marriages, break ups, and other little dramas, as foils for Emily and Louis's drama.
Generosity and charity
Another way of viewing the plot is as a dilemma of charity. When Louis discovers that his wife is hanging out with another guy, he doesn't have the wherewithal to explain to her calmly how that might make him feel. On the surface, it seems that she is offended by his distrust, but the truth of the matter is that they are not really communicating or problem solving like a couple. That's where charity comes in. Charity is the missing key that might help the characters of this novel to work through their drama with more understanding, patience, and generosity. This book is about a couple that cannot give each other the benefit of the doubt.
Youth as a battlefield of love
The most undeniable aspect of the book is how many couples it has. There is no less than 8 separate arrangements or couples, and many of them cheat on each other. When Louis goes to Italy, he finds a new American wife, betraying his own wife back home. But she is obviously betraying him too, and the book never explains why the wife won't quit seeing the Colonel. In other words, she must really like the Colonel. The background characters are in the same mess as the main characters, thrown around by old spinsters who like to match-make. They are constantly trying to find someone to spend their lives with. In this novel, youth is about romance and courtship.
