All perfect praise be to Allah, The Lord of The Worlds, and may His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
Reviling Allah, Allah forbid, nullifies Islam and takes a person out of its fold. Therefore, if it was proven that your wife has reviled Allah, Allah forbid, then she committed apostasy. Consequently, she must immediately turn to Allah in sincere repentance, frequently ask Him for forgiveness, and profess the two testimonies of faith (i.e. I testify that none is truly worthy of worship except Allaah and that Muhammad is the Messenger of Allaah). As regards the ruling on the marriage contract of an apostate, Shafie scholars are of the view that it is tied with reverting to Islam. Therefore, if he reverted before the end of Iddah(Waiting period due to divorce or death of husband), then the original contract maintains its validity, but if he didn`t, but later on repented and re-embraced Islam and wanted to return his wife, then he must conclude a new marriage contract along with a new bridal gift(Mahr).
We(Iftaa` Board) advise the above questioner to be kind to his wife, not to divorce her, but remind her of Allah`s severe punishment. We also suggest that he avoids disputing with her in case she turned to Allah in sincere repentance and re-embraced Islam. However, if she repeated that act, then he is allowed to divorce her, but it is preferable that he checks with the Iftaa` Department first. And Allah knows best.