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.
We have already clarified in Fatwa 82732 that the separation of spouses without divorce does not affect the marital relationship, rather the woman is still considered her husband's wife. Even though the husband has committed adultery, the marriage is still valid.
The wife is not permitted to leave her husband's home without a sound reason, otherwise she is sinful and she must return to her marital home.
Both spouses are required to treat each other with kindness, and fulfil their rights towards each other.
For the rights of spouses towards each other, please refer to Fataawa 83157 and 88304.
Allaah knows best.