Fake case against me

Sir , I'm mahesh and my age is 24 and I was in good friendship with a girl for past 1 year and she used to talk me and we both were good friends , some of her friends created fake account and they texted badly for both of us and after some days they started sending letters to her father like harrassment and in that letter names of boys are mentioned including me , my name was caught in her home and she started avoiding me and she made me bad in her home by saying that this letter and fake account was doing by me , and they believed that , after few days I got this information by one of her friend and I started asking like why u doing all these by making me bad in your home , these is the only thing I used to ask for about 25 days continuously through sms ( 350 sms ) bt she didn't replied, suddenly I got letter to my adress and I was shocked by that content and in that they said that letter will be sent to everyone so I was afraid that if letter will sent to everyone means I'll b the victim so i complained to police station about this and i mentioned that girl name and one suspect boy name , and police called both of them but that girl reversed the story and she and her parents supported that boy and made him innocent, they said I'm the person doing all these , I showed voice records of that girl bt police was not ready to hear and they said why you did these texts , by keeping these we can lodge complaint and we can make you are the person doing all these like that , but I have not texted any bad thing nd I hv not forced for anything and I just asked what's the reason to all these and I asked her to tell truth in her home , this is what I did , for sms I asked apology and I said I won't send any sms and I cleared that matter , now they are saying that if they get any letter means they will give complaint on me it seems.... by keeping that sms which I was did in past , I'm studying for KAS exam , I don't want to get stuck in this fake complaint, I have every msg and voice records of her , and she is relationship with that boy so she is saving him by making me bad , please suggest me what I have to do , if she gives complaint against me like harrassment, after apology I didn't sent a single text .