Abetment to suicide

1. You may prudently marry your girl friend, which will provide you the required legal immunity.

Keep Smiling .... Hemant Agarwal 
VISIT:  www.chshelpforum.com

From the little facts you have mentioned, it's clear that you have proofs against her. So, in the meanwhile if you are really worried then you can approach the police to help you by counselling her and warning her to not threaten you that way. Also it will be on record with a police station before hand so if things go really bad, you can show the acknowledgement of the police complaint and the complaint received by the police as proof. For any further queries or drafting of formal complaint to submit to the police, you can contact me.