Treasures in Heaven — Kathleen Alcala

To escape a scandal that sent her husband into exile, Estela abandons the safety of her hometown and travels with her infant son to the roaring nineteenth-century metropolis of Mexico City. Hoping to begin her life anew, Estela declares herself a widow and goes in search of her former lover - and only true love. Estela's romantic ideals are quickly destroyed; her lover is married, and Estela realizes that to be a woman in Mexico "without family was to be derided, degraded, and disgraced. Born into misery, a woman brought her children into it, ate it with her tortillas, and was buried in it."
When Estela is introduced to an elegantly independent creature named La Senorita, her combination of naivete and intelligence, individual will and compliance is enough to intrigue La Senorita. Born into wealth, and refusing to relinquish control of her considerable funds, La Senorita is a protofeminist whose cause is to fight for "the plight of women in Mexico." Together, the two start an increasingly dangerous movement for social change that foreshadows the Mexican Revolution. It is Estela's ability to take satisfaction from "the repair of the world" that teaches her that the promise of treasures in heaven should never outweigh the gift of a life that is really lived.