Praise be to Allah.
If a man says to his wife, “If you go, then you are divorced,” this is a divorce that is dependent on a condition.
The majority of scholars are of the view that it counts as a divorce if she goes.
Some of the scholars are of the view that it depends on the husband’s intention. If he did not intend divorce – rather he intended to prevent her from going – then it comes under the ruling on oaths, and if she goes, he must offer expiation for breaking an oath (kaffarat yamin).
This is the view favoured by Shaykh al-Islam Ibn Taymiyah, and it is the basis on which we give answers on our website.
Based on that, if the husband says that he did not intend divorce when he said that, or he forgot what he said, and he says, “Assuming that I said that, I did not intend divorce,” then it does not count as a divorce; rather he must offer expiation for breaking an oath.
What appears to be the case from your question is that your husband is certain that he did not intend divorce, even if he has forgotten what he actually said.
Based on that, no divorce has taken place.
But if even we assume that the word of divorce was very clear and the divorce took place as soon as he uttered the word of divorce, meaning that it was not dependent on anything, and he used clear words of divorce, then the woman must count this as a divorce, even if the husband forgot what he said, because a clear statement of divorce which took place immediately is not dependent on what the husband intended.
See also the answer to question no. 116641 .
And Allah knows best.
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