False Allegations and Threats By Girl and Her Family

I'm a 23 year old Guy working in a software company, I had a group of colleagues in the company(Girls and Guys) One of the girl was daughter of influential person , The girl and myself where good friends we used to talk to each other in a very friendly manner,We had been to Outings with our colleagues(group of friends),Having all those things the Girls father caught hold of many pictures which were clicked during the Outings(None being intimidate) They had questioned the girl regarding this matter but never talked to any of the other persons in the pictures, Recently The girl and I had an ugly spat on Whatsapp and I had updated a status to which her parents got involved,They had called the police and the police had called me and threatened me not to abuse the girl on Whatsapp whereas I had not texted her for a month(Influence of Girls father) One of my friend spoke with the girls mom and it was informed by the girls mom that I should block her from Whatsapp and delete her number to which I had obliged,Now after a fortnight she texts my friend and says that I have to return her 10 thousand rupees.whereas there is no proof that I have taken 10k from her I wanted to know how should I prove that I have not taken 10k from her(One of my messages says your money will be refunded to you) Also,If I have to consult police with what Allegations should I present the case And,I'm a middle class working man who doesn't want to get into legal stuff as it may affect my career What will be the simple thing to do legally so that the girl will not bother me anymore further The girl is using all my single side Whatsapp texts to prove that I'm guilty Help me please..