Legal action that can be taken if being threatened

My wife had a affair before marriage. Now she is getting calls from his X boy friends wife and she is threatening that she has photos of my wife and will post it in social media as well as a legal action. I was trying to go mutually with my wife X husband wife but she is threatening me also. And saying that will send everything to my office resident etc.. now I want to live with my wife and having a kid also. But her X boyfriend wife isn’t torturing me on daily basis since from last one month. What can I do kindly advise.