What is the main theme of Carson McCullers' first novel?

Carson McCullers' first novel, "The Heart Is a Lonely Hunter," powerfully explores the theme of spiritual isolation experienced by misfits and outcasts in society. The characters in the novel are deeply affected by their inability to connect with others, highlighting their loneliness and longing for understanding. Each character embodies a different facet of isolation, and their struggles resonate with readers, shedding light on the human condition and the hardships faced by those who exist on the fringes of society. This theme is pivotal throughout the narrative, making the focus on spiritual isolation particularly significant in conveying McCullers' insights into the human experience.