Expecting Face Cases On Calling The Marriage Off (engagement Broken)

I had my engagement in April - 2017 The girl informed me v.little about her past relationships. I found her absurd photographs with other guy from her laptop afterwords. (I have those pictures with me as of now) Then also I was supporting her. But in the month of Aug 2017 she end up with me on the basis of my look and she requested that I will not inform her parents, she will inform her parents on her convenience. (Call recording available) So I just informed my parents of the happenings, meanwhile she created an account on shaadi.com (screenshots are available) Meanwhile I and my parents fixed some other prospectus for me assuming that my ex-fiancee would have informed her parents if not in august then in sept or oct. but that girl informed her family in the end of feb. So her family build pressure on me through her saying that since I got engaged with her I have to marry her. Else they will file a case of dowry and all the possible cases against me. I have screenshot of those whatsapp conversations literary saying that "we will make your employer to terminate you" "we will give these issues in media" "we will send you and your family behind the bars" "we will get your home seized" "you don't know the connections of my family" "you won't be able to survive in this state anymore" etc etc etc. Please guide me what I should do now. What are the charges I can file on her in both the cases e.g. what are the cases I can file if I want to be defensive and what are the cases i can file if i want to put up this matter aggressively. also guide me that what are the possible charges she can file me as of now considering the consequences I stated above. PS1 : They have given me some amount of money to purchase my engagement ring apart of that every expenditure has been beard by me and my father like the ring ceremony function, their travel, staying, fooding, occasional gifts to her (bills available) and the summed up amount is 4 times higher than what they've spent on me. PS2 : The girl wanted to do some professional course before marriage and her father was not in agreement so she asked me to anchor infront of her father than. So they may think that I have encouraged her for that course and all. PS3 : She is showing her self employed at some organization, and splitting out her CV here and there stating that she is earning 20000 rs per month. but I know that she is a ghost employee. Will this help me if they will file a maintenance case .. Will maintenance case applicable if the marriage has not been taken place. And if this is advisable to get married under such situations as date has been finalized and invitations has been gone. What are the additional cases I may attract by marrying in this situation.