How should one deal with a wife who slanders her husband everywhere, denies his favors to her and their children, and incites their children to make excessive demands on their father, especially since she lives a life of luxury?

Allah has commanded justice and benevolence, and forbidden injustice and oppression, and this includes the marital relationship. A husband must be just between his wives in terms of lodging and treatment, and providing only material comfort is not enough. If the injustice originates from the wife due to jealousy, the husband should advise her in the best manner, be patient with her, treat her kindly, and be just between her and her co-wife. The wife must fear Allah concerning her husband, obey him, and respect him. She must not harm him or speak ill of him in his absence, because that is forbidden backbiting. If there is injustice from the husband, she has the right to demand the removal of the injustice or to take her case to a judge.