Was in a relationship with a married woman threatening to case

I am in a relation with a woman for 2 years.She has her husband and a daughter. We had all types of relation.Both of us are in same profession.Now she is going to lodge an FIR with her husband against me that I raped her for two years by threatning and immotional blackmail. She is telling u have to spend behind the bars for life time. And she will terminate me from my job. At this moment what should I do?