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.
Dear brother, you should know that the fact that a woman is not a virgin does not necessarily mean that she had committed Zina (adultery). Losing virginity has several causes as we have previously clarified in Fatwa 86394. Therefore, you have no right to think ill of your wife without evidence, as in principle a Muslim is innocent until proven guilty. Allaah says (what means): {O you who have believed, avoid much [negative] assumption. Indeed, some assumption is sin.}[Quran 49:12] Our advice to you is to strive to repel any suspicions about your wife. Take into consideration her situation now; if she is a righteous woman, then you should live with her in kindness. Not loving her could be due to those suspicions that you have about her. If you repel them, you may begin to actually love her.
Even if we assume that you do not love her, look at what 'Umar said to a man who wanted to divorce his wife on the grounds that he did not love her; ‘Umar said to him: "Woe to you, homes are not built on love alone; where are the care and doing good for others (for fear of disapproval)?"
Also, ‘Umar said to a woman who was asked by her husband ‘do you hate me’ and she replied ‘yes’: "You women should lie (in these circumstances) and say good words. Indeed, not all homes are built on love, but on living honorably with each other in an Islamic way." [Kanz Al-‘Ummaal]
What is meant is that the bond of marriage should not become weak because of unstable emotions or considerations that can be tolerated. It is more appropriate to think of other great advantages of marriage, among which is the fetus in your wife's womb which is a bond that ties you and her. Perhaps Allaah The Almighty may make him a blessed progeny by whom your eyes would be comforted.
If you decide to keep your wife then you should keep her in kindness and not desert her in bed without a sound reason. Rather, a wife is deserted if she becomes recalcitrant. Also, deserting her in bed is not the first step in treating a wife’s recalcitrance.
On the other hand, she has the right upon you that you have sexual intercourse with her according to her desire and your ability. If you are negligent concerning this without any sound reason, then you are sinful, in the same way that if she refuses to answer your call to bed without any sound reason, she would be sinful as well. For more benefit, please refer to Fatwa 90306.
Dear brother, if you do not keep her in kindness, then you should divorce her in kindness. However, we prefer that you keep her if there is no preponderant benefit in divorcing her as the benefit is not always in divorce. You may also think of marrying a second wife if you are able to be just between two wives. For more benefit, please refer to Fataawa 81469 and 84528.
Finally, you should hasten to repent from committing adultery and avoid the causes that lead to it and also avoid the lures of Satan. Contemplate how refraining from what is lawful to you led you to commit what is forbidden. For more benefit, please refer to Fatwa 86527.
Allaah Knows best.