Left my cheating wife and then my best friend of 20 years started dating her?

I caught my now ex wife cheating on me so I divorced her. I did not tell her that I caught her and I did not tell my best friend either because I felt stupid. so now he moved in with her and they are "Dating". the hard part is that My ex and I have a daughter together and he is her god father. What should I do?

Copyright © How To Catch a Cheater