Mental torture, defamation

A lady goes out with a boy and then gets engaged to another boy. Then she lodges a complaint that an unknown person is harassing her and gives the boy's no. in the police station. The boy is called to the police station where he clarifies that he has not done anything wrong and he is not at all harassing her. The girl denies that she knows the boy. After the police counsel, The girl , her fiance, her mother and her brother leave the police station. After a few days, the police again call the boy and the girl accuses him of sending the girls photo to her eldest would be brother in law. The boy in clear tone states that he has not done such a thing nor is he interested in the girl as she is already engaged and about to be married. After a few days, the boy was once again called to the police station but as he was not available, his brother presented himself. It seems the girl and her mother had visited the police station the previous day and had spoken to the Circle Inspector. It seems the girl's fiance broke the engagement and the girl's family is blaming the boy for it and threatening him that if he does not come and meet them, they would be booking a case against him. The boy is mentally disturbed as he comes from a respectable family and the police calling him regularly to the police station and the girl's family hounding him to meet them is taking a toll on his health. Please advise what the boy can do.