GF is blackamailing me to commit suicide if i breakup with her

I was the first love of my GF and I am with her since last 5 years, in between I caught her red handed with hotel room with other guy but after her several apologize, now after 10 months she is doing the same but this time she has 5-6 boyfriends. She has accepted all this and I have call recordings and photos. Now the scene is she is afraid of her parents and society if they will find out her doing. She claims that if her stress level increases she might commit suicide and she will make me responsible. Please help me as how I can save myself. I dont care she lives or dies as i cant love a whore but I am afraid she will ruin me for nothing. pls, help me as what should i do so that police cant claim me for her death (if any). reason is that girl is psycho and even her own sister accepts that.