After 3 months of marraige wife went to parential home

I got married 9 month ago , then we stayed happily for 3 months , then my wife started to convience me that i have to take full responsiblity of her parents and have to keep them in my home and i disagreed to this ,then on completion of 3rd month suddenly my father in law came and took his daughter to his home without my concent , then i kept asking him and my wife to return but they didnt , then after 6 month again came and went directly to police station with false allegations and asking for divorce, then finally she took all her belongins and went to her parental home with a letter to me that its her wish , so i wanted to file a informatory petition , want to know the procedure and will it safegaurd me I will clarify that no complain and FIR has been lodged , instead i have a letter from my wife written in presence of police stating "she is leaving for her parental home on her own wish with all her belongings and there is no fault of anyone and she has no complains to police station." Pls suggest what should be my next action.