enotes provides this answer: ""A Worn Path" is told from a third-person limited point of view. This allows the reader to empathize with Phoenix, because her thoughts and actions are shown. Yet, in third-person, the reader is allowed to view Phoenix from a distance, and thereby see her as others see her." Yes, she is reliable. Her story is a hard one, but we believe it because the cultural background provides evidence for the truth of what she says.