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.
The fact that the two spouses are apart from each other – even if it is for a long period of time – does not mean that the marital bond came to an end. Hence, if the husband did not divorce his wife or a judge did not rule that they are divorced, then their marriage is still valid; for more benefit, please refer to Fatwa 82732.
On the other hand, this husband is Islamically required to have good marital relationship with his wife; Allaah Says (what means): {And live with them in kindness.}[Quran 4:19] Among living with her in kindness, is fulfilling her desires. As regards him leaving her like this, neither divorced nor married, then this is not permissible. Therefore, he should be advised either to keep her in kindness or divorce her in kindness as Allaah ordered in His Book.
Also, among living with her in kindness, is that he fulfills his obligation of spending on her and on his children from her and if he is negligent in this regard without having a sound reason, then he is sinful. ‘Abdullaah Ibn ‘Umar narrated that the Prophet said: “It is enough a sin for a person not to provide means of sustenance to those whom he is obliged to support.” [Ahmad and Abu Daawood]
Moreover, if a husband does not spend on his wife the obligatory spending for a given period, then this does not render him exempted from this spending; rather, it becomes a loan that he is obliged to pay according to the view of the majority of the scholars whether or not he had a sound reason for leaving her. As regards the spending on the children, it is also permissible to ask the father for a reimbursement if the one who spent on them did so with the intention of asking the father to reimburse him for doing so; for more benefit, please refer to Fatwa 85012.
In any case, if a husband did not spend on his wife, or that she is harmed because of him not having sexual intercourse with her, then it becomes permissible for her to take the case to an Islamic judge so that the latter would order the husband to fulfill his obligations towards his wife or rather divorce her from him even in return for compensation that she pays to him. For more benefit, please refer to Fatwa 89039.
As regards the mistreatment which you mentioned on the part of this wife’s in-laws and them transgressing her, if it is true, then this is evil and the husband should have repelled their harm from her.
Finally, it should be noted that the wife has the right in a separate accommodation as we clarified in Fatwa 84608.
Allaah Knows best.