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. We ask Allaah to exalt his mention as well as that of his family and all his companions.
Allaah has legislated marriage for great religious objectives. One of which is to preserve the chastity of both spouses and achieve a psychological stability for both the husband and wife. So marriage has to be looked at as a great benefit and differences or disputes should not prevent the benefits of marriage. So we advise you to study this matter. If it is possible to solve the issue and keep her as a wife then this is good.
However, if you are sure that if this marriage continues, its objectives will not be achieved, then it is more appropriate to accept her request for divorce. You have to know that Islamic Law has put divorce in the hands of the husband, so if you did not utter the word divorce to her, then she is still considered your wife, and the divorce she obtained from man-made courts of law is of no effect. Muslims should be judged by the Law of Allaah and not any other legislation.
Nonetheless, if you accept her request to divorce her, then a divorced woman deserves half of the dowry before the marriage is consummated. As regards, the wealth that you have given to her as a gift, it is not permissible to take it back after it became her possession, because once it is possessed, you cannot take it back.
Finally, we remind you that being alone with her in a house [or flat or room] is considered as having consummated the marriage with her [even if no sexual intercourse had taken place], and in this case she deserves the full dowry and she has to observe the waiting period. If she is the one who wants divorce, you can take a compensation for divorcing her, a compensation on which both of you should agree. This is what is called Al-Khul'. [To agree on a divorce in return for compensation] It should also be noted that a Fatwa is not enough for such issues which are contested. So it is more appropriate to refer to some trustworthy Islamic centre in your country where the issue can he studied and both of you can be heard, and then give an appropriate ruling.
Allaah knows best.