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.
If this husband is as you described in the question, then his conduct contradicts the Order of Allaah about living with one’s wife in kindness; Allaah Says (what means): {And live with them in kindness.}[Quran 4:19] Therefore, this husband should fear Allaah in his wife and children, and he should know that Allaah is able to avenge him. Thus, he should choose between two matters, he should either keep his wife in kindness or divorce her in kindness; for more benefit, please refer to Fataawa 85308 and 88304.
Similarly, we remind this woman of Allaah because it is not permissible for a woman to have an affectionate relationship with a non-Mahram man as clarified in Fatwa 81356. If this happens from a woman who is already married, then this makes the sin even greater. The mistreatment of her husband to her is not a sound reason for her to do so and it is not a sound reason for her as well to prevent him from his right of having sexual intercourse with her. Therefore, she is obliged to repent to Allaah and cut her relationship with that non-Mahram man. Besides, she should give her husband his right of having sexual intercourse with her; for more benefit, please refer to Fataawa 100429 and 88547.
Moreover, she is obliged to obey him in what is permissible as long as she is his wife, among which is that she should reside where he resides if he asks her to do so, and she is not permitted to disobey him. Furthermore, she should know that it is her right that her husband shall not be absent from her for more than six months. However, she has no right to object to him going to work in another town, but he is obliged to leave his wife and children in a safe place. In any case, it is better for the husband to reside with his wife and children and they should reside with him wherever he resides.
On the other hand, it should be noted that a husband should not approve immorality in his wife, so he is obliged to prevent that man from entering upon his wife otherwise he would be a cuckold, and it is forbidden for his wife to let that man enter upon her.
The following two matters should be noted:
1- It is forbidden to spoil the marital relationship between a wife and her husband as already clarified in Fatwa 92056. Indeed, some scholars are very strict about this matter and are of the view that the marriage of a man with a woman whom he was the cause in spoiling the relationship with her husband is not valid; so one should be very careful.
2- The husband’s statement to his wife that he will bring her the divorce papers does not lead to divorce unless the husband intended to initiate divorce.
Allaah Knows best.