To my knowledge the cheating has not taken place yet but I think possibly the dilemma is the same.
A couple I know, been married for approx 13 years, two children, the husband had cheated before. Wife has forgiven him but I don't believe fully trusts him.
Husband nearly cheated again two years ago but didn't go through with it. There is reason to believe he may go through with it within the next month as the person he nearly slept with is back on the scene temporarily.
Wife knows nothing about the last time it nearly happened so no reason to be cautious this time.
Would you warn the wife if you were her friend? Or stay well clear? Would you want to be told if you were the wife in the scenario?