What is the theme in The Ballad of the Sad Cafe by Carson McCullers?

Outcasts are a major theme in this book. Many of the characters in these stories are outcasts and misfits, seemingly doomed to forever be on the outside of society looking in. Miss Amelia is a classic outcast in this mold in "Ballad of the Sad Cafe," distanced from people, a hermit who stays inside and can only relate to people when she engages them in lawsuits for petty matters.