All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
Married partners are required to respect each other, and be patient with each other as we mentioned in Fataawa: 85044 and 85167.
The Prophet said: "There are three things which if done seriously are valid and if done in jest are also valid: marriage, divorce and manumission."
Therefore, if the husband had pronounced the clear words of divorce thrice then the divorce is effective and he can not take his wife back as we mentioned in Fataawa: 85521 and 87352.
However, saying "I will leave you" is not a divorce, but rather a promise of divorce which is not considered a divorce as we mentioned in our previous Fatwa: 89065.
A woman does not have the right of divorce, instead she has the right of Khul’. For more details please read Fataawa, 85034 and 81844.
Allaah Knows best.