Regarding my marriage problem and my wife cruelty&blackmailing

Dear Sir/Mam, I have been married last year in May 2016 and total marriage tenure is 1 years 3 months. I belongs to a middle class hindu brahmin family where parents decision always be in high priority. My marriage also happened with the decision of my parents, even i have not meet my wife before marriage as in our society and culture it is not recommendable. Before marriage my father in law represents wrong and fake things about my wife to my parents (that she is educated, she is very good in all household works, bla bla..) now after marraige when she came to our home we came to know that she is not good in study, she was always sick and ill during her life and suffring with iron deficiency anemia (when we done the checkup as pr report) she never do a single work at her home and also she is very rude to me and my parents, even she also done the dramas several time in our home and broken the family peace. We are really very sad and in trouble as we feel that we gone through a major marrital fraud. Also I tried to explain our home rules and regulations various time to her but always she refused the same and not going to obey our rules. Also after 6 months of marriage she created a very painful situation where her parents came with 4-5 people at our place and threatened me and my mom dad that she will make us in trouble with fake domestic violence case and other cases against a husband. Always they forcefully take a consent on paper from me that " if anything happen to their daughter or if her daughter do anything" all responsibility comes to me and i have to give them that signed consent letter to stop that drama". Now i am very nervous and in fear after giving her the signed consent on plain paper.Currently my wife is 8 months old pregnant and she is at her mothers home. But their is nothing still any change her in attitude nor her family attitude. But i discussed this with one of my legal friend and he suggested me to file a NC complain against her in the local PS for the safety purpose and keep that copy with me for my family safeguarding. Also i have taken her sign on the E-stamp paper which is blank and 3 plain pages ,so that i can make a " Legal declaration and agreement". What all points should i mentioend in the same agreement and where i notarised the same to PS or local court, I just want me and my parents safety as she is very cruel and can create problem for us any point of time in life..please help and guide..