By the time that Louisa ends her engagement to Joe, readers are aware of the fact that neither party wants to be with the other—Louisa because she prefers solitude and Joe because he wants to be with Lily. The fact that both of them act diplomatic in their break-up conversation—withholding the depth of their desires to rid themselves of the other—turns this into an example of dramatic irony.
Though the narrator doesn’t show readers the full conversation between Louisa and Joe, their summary of it captures the irony well:
Louisa Ellis had never known that she had any diplomacy in her, but when she came to look for it that night she found it, although meek of its kind, among her little feminine weapons. Even now she could hardly believe that she had heard aright, and that she would not do Joe a terrible injury should she break her troth-plight. She wanted to sound him without betraying too soon her own inclinations in the matter. She did it successfully, and they finally came to an understanding; but it was a difficult thing, for he was as afraid of betraying himself as she.
Louisa’s intense commitment to wielding “diplomacy” as a “little feminine weapon” so as not to “betray too soon her own inclinations in the matter” and Joe’s similar attempt at not “betraying himself” paints a humorous portrait of two people trying their best to act much more somber than they feel. Though Freeman’s humor is subtle and indirect in this story, this is a moment that she hopes will make readers laugh as they experience the dissonance between how the characters are acting and how they truly feel.