Indeed, I think that a strong case can be made that the entire week in which Shukumar and Shoba are becoming closer, there is greater distance emerging. This is evident with her revelation to him, the purpose of the game, and his revelation to her, the retaliatory response to it. It seems to me that the most likely ending is given by Lahiri herself in the ending to the story. As Shukumar endures the revelation he has received and the one he has given, he takes the plates to the sink and then looks out the window:
Outside the evening was still warm, and the Bradford were walking arm in arm. As he watched the couple, the room went dark, and he spun around. Shoba had turned the lights off. She came back to the table and sat down, and after a moment Shukumar joined her. They wept together, for the things they now know.
In the final analysis, they are bonded to one another out of their shared sense of hurt and misery. I think that Lahiri's indication that this understanding of the other and of self makes it impossible for them to reconcile as they once were. The fact that Shukumar's revelation was so pointed and so direct, even more so than Shoba's, makes it evident that their bond of misery and pain at the hands of another will make it impossible for any redemption to be evident. There can only be hurt and suffering, reducing the likelihood that the couple will reemerge together and unified. Their shared moment of suffering is the sum total of their relationship, the last vestige of togetherness. They are only able to bond through their hurt, pain, and regret. The Bradfords walking arm in arm provides the perfect juxtaposition to the sharing of a couple in happiness and the sharing of Shoba and Shukumar.