Welcome to Psych Central (PC). Sorry to hear you are feeling hurt from your wife's intention to have relations outisde the marriage. Why not talk about this development of a sexual affair with the counselor. Affairs can destroy the basic trust in a relationship and can be a sign that one of the partners is either feeling a lack in the relationship or could be suffering from addictive behavior in regard to sex.
This sounds serious because of how destructive this type of behavior can be to a relationship.
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