Cruelty

My friend had a second marriage post his divorce. He got acquainted with a girl through famous matrimonial website. The girl shared the ex parte divorce details and my friend trusted them completely and got ahead with the marriage. He did not take a single pie and bore all the expenses for the marriage. After marriage within three months he got to know that she had three to four cases on her name(ex parte divorce and the status online says "Revoke" when checked in court they arent able to find papers, property suit with in laws and 498A against earlier husband). The 498A judgement was out just three days before the marriage. All these details were hide by girl and her family to him. He should have throughly enquired before getting into this mess. Now with in three months of the marriage she started abusing him and his brother's family who stay together in one pretext or other.She started meeting neighbours and making false allegations against him and his brother's family saying they took away her gold, wont give food etc where in fact she has never brought anything nor she has given away food at home...She herself is threating mental cruelty case against them. My friend and his family are unable to bear the torture, they requested her parents to take her back home and keep her for few days for which they are against. Looking at her words, gestures they are all frieghtened and unable to think of solution. The second marriage is just three months old. They are feeling threat from her. She changes her words as per her requirement.Please advise on the best possible options.[Cheating ? Judicial separation? Police Complaint? ) my friend has decided to get divorce or separate from her.