Is it permissible for a woman to refuse to return to her husband who curses God and commits acts of disbelief when angry, and who has previously divorced her twice, knowing that she is now in the waiting period (iddah) of the second divorce?

The husband committed a grave sin by disbelieving in Allah Almighty, because insulting Allah is an act of disbelief by consensus. Anger does not negate accountability unless it leads to unconsciousness. Therefore, he must repent and return to Islam. As for his statement, "If this happens, then you are divorced," divorce occurs when the condition is met. The wife, if she is in a revocable divorce, has the right to seek khul' if she dislikes remaining with her husband. The husband is advised to avoid anger, and the wife should avoid provoking him.