why did jeannette walls think her family abandoned her

While driving away from the casino, Jeannette falls out of the side door of the car and tumbles down a desert hill, bloodying her nose and getting pebbles and debris stuck in her skin. She waits for a long time by the place where she fell, fearing that her parents might abandon her. When her family finally returns, Jeannette refuses a hug from her father, blaming him for trying to leave her behind forever. I think this is just another example of her parent's complete disregard for anything coming close to responsible parenting. There is a sense that her father and mother are oblivious to their daughter's safety and sanity.