If you are friendly with a husband and wife (equally) and you happen to discover that the husband is cheating, would you tell the wife somehow?

Additional facts:

-you discovered the affair accidentally (...saw them at the movies)
-the husband does not know you know
-your own husband (a conservative accountant for PWC) knew about the affair beforehand but never told you about the affair because he says it is none of your business to begin with.
-your husband is pissed off at you because the last time you saw the wife, you gave her a long strong hug for no apparent reason

Karma should take care of things in the long run but in the short run, i have no clue what to do.

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Jennifer
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