What can I do if girl's family threatens to kill me if I marry their daughter?

I am married to my wife through court, it’s been 6 months now we haven’t told anyone till, i am at my home and she is at her home and we want to live together if i will inform girl’s parents about the marriage, they will kill me and my family, i even tried to talk to her father on phone he told that if i will come there he will kill me and go to jail i need suggestions.