Hazrat Aisha (may Allah be pleased with her) says that divorce takes place only after marriage. Hazrat Zuhri (may Allah have mercy on him) says that divorce will occur only when there is a marriage.
Hadith Referenceمصنف ابن ابي شيبه / كتاب الطلاق / 18767
Hadith Takhrij(مصنف ابن ابي شيبه: ترقيم سعد الشثري 18767، ترقيم محمد عوامة 18117)