If I understand your question correctly, Willa Cather’s My Antonia (1918) would be a good candidate for studying the mind and heart of an American writer. This novel, while fiction, deals with the alienation of the heroine from her youth in Virginia to the Midwest, an experience shared with the young Willa Cather, at a time when women American writers were still establishing their unique contribution to American literature. Set in the 1880’s, Antonia, age 8, moves with her family to Nebraska, as Willa did. The novel is really a collection of short stories about Willa’s experiences up to the time when she began her career as a writer. Considered today as a fine early expression of female emancipation, feminity/sexuality, and social and historical commentary on the variations of life west of the Mississippi, it is both a quasi-autobiographical novel and a historical record of the late 19th century in America.