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.
Firstly, defaming the chastity of a Muslim woman is a serious matter and doing so without evidence is an irresponsible act which a Muslim is not permitted to resort to; for more benefit, please refer to Fatwa 87225.
Therefore, if your in-laws accuse you of something you are innocent of, then they are sinful. Allaah Says (what means): {And those who harm believing men and believing women for [something] other than what they have earned [i.e. deserved] have certainly born upon themselves a slander and manifest sin.} [Quran 33:58] Thus, you should remind them of the seriousness of this and the obligation to repent from it. Besides, if a person is accused of something, he has the right to defend himself and prove his innocence.
Secondly, the husband is obliged to spend on his wife and he is not permitted to be negligent about this as we clarified in Fatwa 85012. If the wife spends on herself from her own money, she has the right to ask her husband to reimburse her for it even if this had happened so long ago.
Thirdly, the statement of the husband to his wife: “I will divorce you today” is not considered as a divorce, but it is only a promise of divorce. For more benefit, please refer to Fatwa 92383. Also, his statement to her “I do not want to live with you” is one of the metaphors of divorce by which divorce does not take place unless the husband had intended it.
Fourthly, the son is not obliged to obey his parents in divorcing his wife if they do not have a sound reason for that. For more benefit, please refer to Fatwa 84056. However, if he obeys them and divorces his wife, the divorce takes place in any case. Nonetheless, divorce is not desirable if there is no sound reason for it. Indeed, some jurists are of the view that this is even forbidden due to the disadvantages that it leads to. For more details, please refer to Fatwa 87786.
Hence, if reconciliation is possible and the wife can return to her husband, then this is good, otherwise she should forget him and ask Allaah to bless her with a better husband. Allaah Says (what means): {But if they separate [by divorce], Allaah will enrich each [of them] from His abundance. And ever is Allaah Encompassing and Wise.} [Quran 4:130]
Fifthly: If the marriage contract is concluded while fulfilling its Islamic conditions, then it is a valid marriage contract and its effects take place whether or not the person conducting the marriage contract intended it, as the Prophet said: “There are three things which if they are done seriously they are valid and if they are done in jest they are also valid: marriage, divorce and taking back a wife (to marital bond after divorce).” [Abu Daawood, At-Tirmithi, An-Nasaa’i and Ibn Maajah]
Sixthly, the husband is Islamically required to treat his wife in a kind manner and to fulfill her rights in the same manner that she is obliged to fulfill his rights; Allaah Says (what means): {And due to them [i.e. the wives] is similar to what is expected to them, according to what is reasonable.} [Quran 2:228]; for more benefit, please refer to Fatwa 88304.
Seventhly, the statement of the husband about his father that he is god for him is a very serious statement. If he really means it, then this is disbelief in itself; however, if he only means exaggeration in him being keen on implementing his orders, then this is not considered disbelief, but it is an outrageous and abominable statement which he must avoid in the future.
Allaah Knows best.