Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- You haven’t clearly illustrated if she just signed that affidavit or she lived with that man and committed adultery with him. If she has done all this, you can divorce her leaving the judgment to Allah Almighty either in this life or in the Hereafter.
2- However, if she has just signed that paper and there is any legal way to reconcile the matter, and also there is some hope you can return to each other, you can seek help from trustworthy friends to do that.
In his response to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
If what you allege about your wife is true, then she is guilty of adultery and breach of trust. If she is living with another man without lawful marriage, she has also committed a double offence by faking the marriage.
None of her sins, however, is your problem. If you have not contributed to any of these, then you should simply part ways by divorcing her. No person with a conscience can tolerate such behavior from his wife.
Leave the judgment to Allah. He has decreed that those who break His laws will be broken by them.
Allah Almighty knows best.
Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.