How to prove my innocence against a fake domestic violence case

my wife complained to state control of gujarat that im physically mentally torturing her and then ankleshwar(gujarat) police came and enquired both of us.in talks with my wife in presence of police my wife didnt filed any case and wrote a letter that due to misunderstanding i complained to police and i dont want to file any case .then she is saying now that i will go to my home town and file a case again on you mean while my wife parents came and taken her to her home in presence of police giving a letter.at that time my wife said i didnt done any thing in this between so if she files a complaint again in her hometown(vuyyuru-vijayawada) does this case stand? and can i show the copy of letter what she wrote in ankleshwar police station and how can i proceed and how can i prove im not guilty kindly assist me in this matter