My wife recently confessed that she'd fucked one of her male best friends before we were together. She said it was just a one-off fling 6 years ago and they have been friends for 12 years with nothing else sexual happening....

I said well i'm not going to leave you but you know what i am going to do is find another woman to sleep with so i can even the score kind of thing. She agreed at the time but now it's the time for me to meet this woman tomorrow and bring her home while my wife stops at her friends and now my wife is putting up some resistance saying she's nervous and what if i decide i 'like her better' or want to stay with her instead etc. I assured her it will be just a fling, just sex like you had with your male friend but still she is fussing asking what sheets will be on the bed, will she stay the night after the sex and stuff.

I never interrogated her about the male friend (who is still very much around and part of her life by the way) now i feel like i am answering questions and dealing with too much stress about this....

your suggestions?