Why has buds mother left home bud not buddy?

In "Bud, Not Buddy" by Christopher Paul Curtis, Bud's mother left home due to the hardships of life during the Great Depression and the struggles of raising a child alone. She believed that leaving was necessary for Bud's well-being, hoping he would have a better chance in life. Her departure is a pivotal moment that influences Bud's journey to discover his identity and find his father. Ultimately, her absence symbolizes both loss and the search for belonging.