To conclude the question your answer would be, Man vs Society.
One of the first hints we can find about gods in Nectar in a Sieve is found in Chapter 3, when Rukmani talks about the difficulties her and her partner, Nathan, have to conceive a child. In her visit to her mother, who is a very spiritual person, Rukmani criticizes the god's willingness to help human beings:
"My mother, whenever I paid her a visit, would make me accompany her to a temple, and together we would pray and pray before the deity, imploring for help until we were giddy. But the Gods have other things to do; they cannot attend to the pleas of every suppliant who dares to raise his cares to heaven. And so the years rolled by and still we had only one child, and that a daughter."
Another example of Rukmani's reference to gods, is found in her description of her youngest son's health condition, as well as her struggling to help him. This can be found in Chapter 16:
"I gazed at the small tired face, soothed by sleep as it had not been for many nights, and even as I puzzled about the change, profound gratitude flooded through me, and it seemed to me that the Gods were not remote, not unheedful, since they had heard his cries and stilled them as if by a miracle."
Initially Valentine tells says that the two boys are opposites: Peter is a killer and Ender shows empathy. However, as the novel progresses, Ender is beginning to see himself as a killer rather than a sensitive boy who can show empathy.
