harassment...

Approach Cyber crime branch of police and file a police complaint giving all the details.After investigation if police find the caller has been cheating , they will take action against the caller and all concerned.

As per your query, I would suggest you that as this point you must save all the chats that and text conversations that you had with her, moreover if you get in touch with her via call try to record your calls in order to connect to the type of conversations that takes place.

Audio's and even screenshots of messages (including messages on social media applications) can be used as evidence in as suit as per the Supreme Court of India. Thus, try to fetch all the conversation (both text and calls), for presenting it before the court of law.

Hope It Helps!

Regards
Kevin M. Paul