I want divorce from character less wife

I have marraige before 10 years and we have 6.5 year old boy. my wife has an affair from last 4 years. she talks everyday on mobile phone. We have collected last 6 months call details and its proved she talks with him. He also confess she was talking with every night. now she comes with me. she had try two times suicide. and I also inform her father and mother. and also she give me threatening several times she become suicide. can we take any written from she or what is other ways to short out this problems. Her father wants divorce. but she tell that i will come at your but i cannot given written .