Note : I don't reccomend using the word "trying to " when you are talking about protecting your marriage. Don't sweat it, but in the future just leave it as
I AM protecting our marriage. If you saying "trying to" it sounds like you are apologizing and that you did damage instead.
You need to be VERY solid on these points to get your message across. They only absorb maybe half of what you ahve to say, so you need to be as clear as you can. You can also mention that when SHE dolls herself up and talks to HIM about YOUR marriage in private it humiliates YOU.
I had this issue with my wife too.. she didnt like me violating HER privacy when i was researching her affair. I simply countered that SHE was talking about MY MARRIAGE in PRIVATE with OM without MY CONCENT... which violates MY PRIVACY
So... if she says SHE was humiliated again, don't apologize. Just tell her that marriage problems should be discussed with a Family Therapist and speaking with male co workers should not be done in private. THAT humiliates your husband when you do THAT, AND it humiliates her because it spreads GOSSIP in the workplace.
THEN you tell her you are sorry she feels humiliated, add that YOU are sorry YOU were humilated and had to show up there. Then you tell her you WOULD do it AGAIN to protect HER and your marriage.
THAT is the best way to put that fire out I think.
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If she is INVITING to conversation, you could just ask her outright...
"I have a female friend about my age who wants me to meet her for coffee to talk about her marriage problems... are you ok with that?"
My GUESS is she will say "NO"... but you ahve to be VERY careful here... if she says YES, then YOU look like an ass...
I tried this at home and it worked out well... my W Agreed talking in private about your marriage with an attractive member of the opposite sex is NOT a good idea.
YOu need to get your WIFE to understand that too. But be careful that doenst turn on you.
If she DOES tell you she's ok with it you just say :
"Well you shoudln't be... people CAN and DO have affairs... and VERY OFTEN its from someone at work or a freind who is havign marriage problems or something... if a friend you find attractive needs marriage advice, you send them to your SPOUSE or talk to them with your SPOUSE present ONLY... you don't talk to them in PRIVATE behind your wife's back... I would NEVER do that to you... And I ask the same of you... Its a matter of respecting your partner"