In the story "The Management of Grief," what was revealed about the culture and customs of the characters involved in the story?

Bharati Mukherjee's "The Management of Grief" tells the story of Shaila Bhave, an Indian woman living in Canada who has just lost her husband and sons in a tragic plane crash. The story was written in response to the real crash of an Air India flight from Toronto to Bombay in 1985; it is thought that the crash was the result of a bomb planted by Sikh terrorists who wanted to regain the Sikh homeland in the area of Punjab in India. Mukherjee's story, told from Shaila's point of view, explores responses to grief; more specifically, it explores how an individual's culture, and cultural clashes in a cosmopolitan world, can impact the grieving process.
Early in the story, Shaila is recruited by Judith Templeton, an official appointed by the Canadian government, to reach out to families who lost loved ones in the crash. She is chosen because she has not been exhibiting any odd behavior and is considered by others in the community as "the strongest person of all" and "a pillar." She is also a good candidate to help Judith communicate with the Indian families because "complications of culture, language, and customs" may prevent Judith from being successful. This is the most explicit detail in the early part of the story indicating that cultural diversity will play a role in how the surviving characters will process their losses. 
We also hear some background on Shaila's family. However, most is reserved for the families of her friends; she is more reserved when talking about her own children and husband. We learn from this background, though, that the Indian families living in Canada incorporate influences from Indian and Western/Canadian culture. For example, Kusum, a neighbor of Shaila, has two daughters, one of whom is very Westernized (she likes the mall, McDonald's, and dating Canadian boys), while the other is more traditional ("she sang bhajans for Ethiopian relief"). The parents' generation is more traditional; they are the ones who have immigrated from India, so they grew up immersed in Indian culture. Kusum and Shaila, for example, both married men who were chosen for them (in arranged marriages) and do not outwardly express their feelings to their husbands. Shaila does not even feel comfortable calling her husband by his first name, Vikram. After he is killed in the plane crash, she writes a note expressing her feelings that she then "let fall into the calm, glassy waters." Her grieving process is much more internal than that of the other characters and that is partly a result of her cultural background. Since she stands out from others, though, it is clear that her behavior is also based on her personality.
Eventually, Shaila returns to India to lay her husband to rest in the traditional Indian manner. Men whose wives died in the crash are encouraged to remarry quickly, as is "the call of custom." Widows, on the other hand, are shunned, so Shaila does not remarry. While in India, Shaila has an interesting experience: "My husband descends to me." She later recounts feeling bliss at this mystical interaction with her husband from beyond the grave. This seems to be part of her grieving process, but she does not tell Judith. We can infer that Judith would see this as a red flag. When Shalia goes with Judith to talk to an elderly couple who cannot accept the deaths of their two sons in the crash, Judith shows no sympathy for their mother. She vents to Shaila that "their stubbornness and ignorance are driving [her] crazy." Shaila, however, feels more connected to the family. She asks Judith to let her out of the car; Judith does not understand the plight of the elderly woman nor that of Shaila herself. Shaila reflects, "In our culture, it is a parent's duty to hope." We even saw Shaila doing the same earlier in the story when she brought a suitcase full of clothes for her boys and told an officer that the boys are strong swimmers; she maintained hope that they had somehow survived.
The final role culture plays in Mukherjee's story is in the complex relationship between Shaila, other Indo-Canadians, and Sikhs. The elderly family that Shaila visits at the end of the story is Sikh. She thinks they will not relate to each other, especially considering they are in Canada. Shaila suggests that much of the population is prejudiced against Sikhs now. Ironically, she feels more connected to them than to Judith, and the common culture is part of what establishes that connections. In sum, Shaila's Indian culture influences her grieving process and informs how she connects to other survivors.