Adultery is also what I believe the end is hinting at, especially with the lines: “for a moment it felt good to be touched by someone else” and “but she pulled him back by his arm and steered him to sit on the bed” both lines implying that Darla and Trevor’s relationship is turning from friends to lovers. Darla also lets go of her “fear” of showcasing her body and lets Trevor see her completely naked body since she doesn’t really care about anything anymore, she has completely given up on her relationship with Jon.
The short story takes place at Mandy and Trevor’s house where they are hosting a pool party. Darla immediately notices that all of their photos are of their baby and there is none of Mandy and Trevor, a lot of the pictures is the same pose just in different sizes, which suggest that they don’t really care for each other and are only staying together for the sake of their baby.
In conclusion: both couples are in unhappy relationships and are barely staying together. The