Who is responsible for supporting a divorced woman who has reached an age where she is unable to earn a living, has no wealth or children, and has spent her life serving her ex-husband?

Her parents, if they have the means, are responsible for her upkeep, then her brothers, then the rest of her heirs. If she has no one to spend on her, then her maintenance is from the Muslim treasury (Bayt al-Mal) if it exists; otherwise, it falls upon the closest Muslims, one after another.