blackmailed by a girl

i came to my native place in 2011. A girl felt in love with me. She used emotional tactics and even cut her wrist twice to make me accept her proposal. finally in 2013, i accepted to take my parents in confidence. In Aug. 2014 we made informal engagement but Nikkah has yet not taken place i.e, we r not married yet. After few months of engagement I realised that the girl was not emotionally be fooling me but keep the arrogant arrogant attitude in reality. i found her uncivilized, adamant, arrogant and dramatic nature frustrating me. she tried to seduce me by kissing me many a times, even i responded twice but we never had intercourse. she made big issues if i didnt picked the phone for busy schedule. For meagre reasons she made harrassing visits to my home which put my reputation at stake. she even attempted a suicide for which she was fined by the court of law. she is even harrasing me by visiting my office thereby putting torturing my mental stability and putting my reputation at stake. she even disrespected my entire family. after making thorough considerations i have decided to breakup. now she is threatening me of committing suicide and taking police action against me. she even tried to register complaint against me. she is making my living hell. please help