Hello! You asked about the impact of cultural displacement on the characters in "Mrs. Sen."
1) Mrs. Sen
It is obvious to Eliot that Mrs. Sen misses her home in India. She finds it difficult to adjust to the cherished notion of western individualism and the concept of personal space in American culture. Mrs. Sen misses just being able to call out when she needs something: in India, an expression of any kind, whether of sorrow or joy, would immediately bring around concerned neighbors willing to minister comfort and/or extend needed companionship. It is not so in America.
Mrs. Sen resorts to personal rituals such as wearing saris and painting the bridal vermillion powder on her forehead in order to hold on to her Indian identity. Despite this, it depresses her that there are no suitable occasions to wear her most cherished and beautiful saris. Despite Mr. Sen's insistence that she learn how to drive, Mrs. Sen is not overly enthusiastic about the experience. In India, Mr. and Mrs. Sen retained a personal driver for their needs. In America, Mrs. Sen finds herself overwhelmed with the fast pace of life.
She has to step outside her comfort zone; the multitude of cars on the road distresses her almost beyond endurance. Mrs. Sen regresses to an almost child-like dependence on Eliot. She confides to him her frustrations, fears, and many struggles to assimilate into American culture. In the end, out of an equal combination of desperation and rebellion, she decides to take the car to the fish store, beyond the route boundaries Mr. Sen had set for her. Mrs. Sen sustains a small injury in an accident when she briefly loses control of the car. Her desperate act is indicative of her need to maintain some sort of autonomy and control over her life despite the overwhelming onslaught of foreign cultural expectations foisted upon her.
2) Mr. Sen
He is portrayed as a college professor who is so busy with his teaching career that he is mostly oblivious to his wife's private griefs and struggles. It is Mr. Sen who decides that his wife has to learn how to drive. Faced with western cultural mores, he has to encourage his wife to embrace a feminine independence foreign to both of them. One suspects that Mr. Sen's almost religious reverence for work may well be a coping mechanism.
Despite Mrs. Sen's fondness for fish, Mr. Sen tells his wife that she must stop cooking so much fish for a while. He suggests that she cook chicken instead, as he has to start holding office hours for his students. In India, many families eat fish daily, unlike in America. Later, after the car accident, Mr. Sen steps in to resolve matters for his distraught wife; he finds himself apologizing on behalf of Mrs. Sen and writing out a check reimbursing Eliot's mother for November's child-care payment. In this respect, he finds his husbandly duties just as relevant in America as in India.
Hope this helps. Thanks for the question.