Do Shoba and Shukumar have a future together?

It's difficult to see how they can have a future together. They've been drifting apart for some time, and it's unlikely that a few more power cuts will be enough to get them talking again on a permanent basis.
More importantly, however, is the matter of trust. By revealing the gender of their stillborn child, Shukumar devastates Shoba; more than that, he betrays her. He knows full well that she never wanted to know this information, yet he still goes right ahead and tells her anyway, as he no longer loves her. If Shukumar no longer loves her, then it's difficult to see how the marriage can possibly survive.
For her part, Shoba reveals that she's signed a lease on an apartment so that she can have her own space away from Shukumar. It's perfectly clear that Shoba has already separated herself emotionally from her husband; all that's left to do is the physical separation.

In Jhumpa Lahiri's "A Temporary Matter," the main characters Shoba and Shukumar go through a difficult tragedy. They respond to the stillbirth in different ways, and six months later, Shoba still seems incapable of recovering fully from the loss of their baby. The trauma of the stillbirth has impacted her marriage to Shukumar in ways that the reader, like any outsider who learns of their hardship, cannot fully understand. Though outsiders and readers alike can speculate upon the possibilities of their futures, together and separate, only Shoba and Shukumar know with any certainty whether they still have a future together.
The ambiguity of the short story's ending is part of what makes the story so powerful. Literature is sometimes expected to guarantee a tidy ending for readers; after all, the writer seemingly has full control over the fictions that appear on the page. Lahiri's ability to imitate the confusion and precariousness of real life on the page is what sets her writing apart from the literature of tidy endings; real life is far from tidy, and real life is Lahiri's literary speciality.