What is the ruling of Islamic law concerning a woman who requested khul‘ (divorce initiated by the wife) after her husband discovered her relationship with a male colleague at work?

A woman's relationship with a non-mahram man is a sin, and if she is married, the sin is greater due to her defiance of her husband and her rebellion. It is impermissible for her to seek khul' (divorce initiated by the wife) without a valid legal reason. The husband has the right to refuse to divorce her until she ransoms herself from him. If separation occurs, she has no right to custody of her children until she repents from her immorality. This story is evidence of the danger of mixing between sexes at work, and that what a woman earns due to such sinful relationships is unlawful. Since the khul' has taken place, seek a righteous wife and supplicate frequently.