Divorce - ADULTERY

How to prove whatsapp back storage in gmail as valid proof. Aldo suggest me how to get call detail from family court. After marriage my wife shares her photo by wearing night to his boy Friend and she had done mobile recharge to him. Also additional she had transfer 5000 to his account . They both talk and share about our bedroom and family things happening in my home. This all happen after i go to job. When i noticed she said that he is like a brother. I asked whether brother will be sending message with bad words and why you share photo to him. She is saying that he had love failure and he became mental. He says if you do not send then i will cut my hands and i will die. These i came to know after her 6 month of our marriage life. At time she was pregnant and she said after child born i itself give divorce to you. I accepted. In whatsapp messgae to him, i saw - Due to my family i am accepted to marry him and also its not my wish. How to make proof of whatsapp message backup in email