I believe in controlled exposure, at least that is what worked for me. before I even confronted my h, I told my best friend (who happens to be an IC) and my sister. I was in SHOCK and needed to talk. I held nothing back, gathered information/proof of the affair, and even shipped it off to my sister in VA (had no idea whether him having an affair would affect a possible D if we went that route, and didn't want to give him a chance to hide anything). eventually I talked to both my mother and his mother. I'm very close to his mother and she was devastated by the affair, but at the same time I learned just how much thicker blood is than water.
I pretty much kept it there. eventually told a couple of other close friends, one who I needed help with childcare so I could make IC/MC appts.
I did NOT go to his work, or to his business community (they did work together). turns out many of them knew anyway (he didn't realize that till much later, so funny how sly people think they are).
for me, I needed some people to know because I needed support. but I also wanted to keep a safe path home to my H should he choose to take it.
eventually when the affair didn't end, after many promises that it had, I asked for a separation. he eventually moved in with her, and reality set in for both of them. nothing takes the edge off a fantasy than reality.
in a nutshell, I am happy with how I handled things and have zero regret on that front. glad I told who I told, and glad I didn't bring a ton of people into it and we were able to reconcile.
good luck with whatever you decide!
M-41 H-38 M-10 years, T-14 years Bomb-PA 3/19/07 Separated-6/7/07 Piecing/h back home 5/08 S-6 S-4 D-4
"Courage doesn't always roar. Sometimes courage is that little voice at the end of the day that says, 'I'll try again tomorrow.'"