Mutually divorce

We are married for last 12 years and have one daughter aged 10 and due to loss in my business my wife have made up her mind to marry with some person and is in touch and visiting his house . This fact came to my knowledge just before two months and she is asking me to apply for mutually divorce and simentously wants to remain with me for 6 months as to establish my business like having home and cash of forty lacks. The person who is NRI is financial sound . As per law it is probably menditory to mention that we are putting separately for one year . Where as she wants to give me 6 months and show our application to his new man so that she asks him to wait for 6 months While I have checked that the man has told his neabours that she is his wife and my daughters as his daughter. So kindly advise me what step has to be taken so that my daughter shall be saved from our love and affection. Should I file case for divorce and enter into one more agreement with my wife that we are living together and has two conditions like house and cash . Please advice as my daughter is under distress. The story has this relation has been informed to me by my daughter as my wife was taking her daughter to his new man's residence and confirm this . Even in my presence she asked her mother that how my father is different from her new man .