What would be the best way for me to handle this situation?
Johnny,
You probably don't realize it, but you've just helped your situation greatly (on instinct alone). You have established "the intent of" NO CONTACT (NC) ... the Affair (A) has been broken and your Wayward Wife (WW) appears remourseful.
First ... could you provide us a little background?
You've been married for 24 years ... any children?
You say the Other Man (OM) works in the same building ... is it for the same company?
Is OM married or have a serious girl friend (GF)?
How long was the A?
Where did it occur? (i.e. hotel, car, office, YOUR home?)
IS THIS THE 1ST A FOR YOUR WW? (that you know of)
Does she claim "feelings" for the OM or was this just a non-romantic tryst?
My guess is you don't know (or haven't even considered) some of these ... no problem, completely understanable ... but they are important.
Time to snoop to get intelligence ... get her cell phone and check the history and saved text messages ... does she use a home computer, if so, check her emails, etc., EXPECIALLY THE DELETED AND SENT folders ... waywards have a habit of deleting incoming messages from OM, but they forget to empty the trash or delete their own "sent" messages (THIS IS HOW I CAUGHT MY FWW) ... get her cell phone history to see the extent of her contact and to confirm when contact ceased (if it truly has).
That's a good start, but there will be more to follow.
NOW, keep you head up, you have done NOTHING wrong and a lot of stuff RIGHT. Your proactive stance has improved your chances more than all of the plans described here. We have seen it over and over ... Betrayed Husbands (BH) who act proactively and with a purpose have a chance, those that are too afraid to act ... have NONE.
One last HUGE question ... at this point and with only this minimal information ... what is your gut instinct telling you ... do you want to attempt Recovery (R) or are you more inclined to proceed towards Divorce (Plan D) or are you still "in between"?
Keep in mind there are no right or wrong answers ... you can try to R or you have every right as a BH to dump her and move on ... ITS YOUR CALL.