Girl threatning to commit sucide

I have a friend from 3 years recently when i proposed she rejected me,,and again she proposed i said i cant because my family will not allow.she said its ok lets meet as she feel to drink she called me...i bought drinks to drink she kissed and hugged me and in depression she applied burned cigar on my left hand,..and used knife to cut me...then i decided to not to meet her anymore.. later i stopped to meet her and contacting her, i said i dont want to meet her anymore,after a 2 months i got married in my caste girl.. i never informed this to her ...later again she started to calling me ...i said her that i got married wife also came to knew about my she is threatining me that she will commit sucide...i dont know what to do and how to handle situation and most important point i have not promised her about doing marriage our relationship age is 2 to 5 days ..i said her confim that i cant marry within short time..i never asked her to wait or never asked her to love me....and i do not done sex with she is doing continous calls and saying she will do sucide.