Boyfriend's ex-wife

Hello, I used to work at a company where my senior who was married at that time started liking me. But then he disclosed this thing to his wife and they divorced each other mutually in 2013 jan. Motion 2 also happened without any issue in following oct. During last Diwali, his ex-wife approached me saying that the man is playing with me and all which was not true because I got some evidences. In June, I talked to her to tell her that I had the evidences that she was lying. She in turn filed a case against my boyfriend and family for mental harassment which was being settled under "out of court settlement". I recently happened to talk to her in a very polite way and asked her few things that too in a decent way without telling my boyfriend. Now, my problem is she is threatening him and his parents that if I talk to her, she will file case against them of mental harassment. I want to ask if talking to her is crime? And is there any way by which I can have a court order that she can't file a case against me ,