Suwayd bin Ghafalah (may Allah have mercy on him) said: Aishah bint Khalifah al-Khath'amiyyah was married to Sayyiduna al-Hasan bin Ali (may Allah be pleased with him). When Sayyiduna Ali (may Allah be pleased with him) was martyred and allegiance was pledged to Sayyiduna al-Hasan (may Allah be pleased with him) for the caliphate, he came in to her, and she said: Congratulations to you on the caliphate. He said to her: Do you show gladness at the killing of Sayyiduna Ali? Go, you are divorced three times. So she covered her head and face with her shawl, sat in a corner of the house, and said: Listen, by Allah! I did not mean what you understood. Then she remained there until her waiting period ('iddah) was complete, and then she moved away from him. He sent her the remainder of her dowry (mahr) that he owed her, and a parting gift (mut'ah) of ten thousand. When the messenger brought that to her, she said: A small provision from a departing beloved. When the messenger returned to Sayyiduna al-Hasan and told him what she had said, Sayyiduna al-Hasan bin Ali (may Allah be pleased with him) wept and said: Had I not heard my grandfather, the Messenger of Allah (peace and blessings be upon him), or heard my father narrating from my grandfather, that he said: "When a man divorces his wife three times at the periods of purity, or divorces her three times without specification, she is not lawful for him until she marries another husband" - I would have taken her back.
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2744