At eNotes we can't write your homework assignments for you, but I will offer some ideas which hopefully you can draw upon to complete the assignment yourself. This poem was first published in 1993, in a collection of poetry entitled, "The Latin Deli: Prose and Poetry." This is a collection which reads like a memoir, chronicling the author's experiences as a Puerto Rican growing up in the United States.
The poem is set in the eponymous Latin deli, and focuses on the woman who works there, and also on the customers who frequent the deli. The customers are described sympathetically as lonely, fragile people who miss their own countries. They are exiles from their own countries, and they come to the deli to buy products which remind them of those countries. These products are from "places that now exist only in their hearts."
The woman who works at the deli is kind to the customers, and is called, as such, "the Patroness of Exiles." She seems to be a rather caring, maternal figure. As well as selling products to the customers, she listens to them and offers them momentary companionship. She "smiles understanding" and looks upon the customers with a "look of maternal interest."
Thematically, the poem is about nostalgia and loneliness. The word "nostalgia" derives from the Greek words "nostos" and "algos," the former meaning to return home, and the latter meaning to suffer pain. The customers in this poem are nostalgic for their homes. Their longing to return to their home countries causes them pain in the form of loneliness. This poem is also about the importance of momentary companionship to those people who are displaced, and without a place to call home.