Lurking again Wow...I applaud you for what you did w/the OM...that shows you are willing to continue to stand and how SAD the kids are getting the view that marriage is 'just a piece of paper'...
I'm not sure you are powerless. Tell her you are going to inquire of the courts for them to appoint a guardian ad litum (sp?) for the kids. That clearly having another man in their life while she is still married is NOT in their best interests and is affecting them emotionally-severely. Personally, at this point, I don't think you have anything to lose. She is stubborn, very stubborn...and is being beyond selfish in justifying this mess to the kids. Tell her he threatened you, you have the texts ...let her see that this jerk is not worth it.....if your state is an 'at fault' state for divorce, find the state website, copy the part about filing on grounds of adultery and how it can affect custody, child support, etc. and FORWARD it to her...
God, let me tell you...if my ex had fought 1/2 as hard as you did, he would have had a good chance. And there was no OP in our situation. You are a strong man, your integrity is awesome...I hope you know, whatever way this goes, your kids will recognize all you have done & respect you SO much for it...very sad your wife is willing to sacrifice her self-respect for a POS.