Heading toward affair- what to do?

[hopeOK]

Well I've gone through all the calls & texts on the account. None w/ the OW number. However, there are a bunch of texts & some calls (one 14 min long) w/ a co-worker that I saw he recently friended on fb. She is a very attractive girl. He left his fb signed in one day & I saw where he had searched for her like 6 times in one day. Then they became friends. I unfriended her on his fb w/o him knowing. I saw a couple days later that he had searched for her twice after I had unfriended them. So I'm sure he was wondering what happened & thinking she dissed him. Maybe that was wrong of me but ah well. So not sure if this is all business or if there is more to it.

Another call that occurred once was to a girl that he knew from a previous job... 8 minutes long, he called her. This particular girl i had no idea about until after the affair was discovered & he gave me complete access to his phone. I saw that there was a message from her on an email account that he didn't use much... her telling him that she was about to get married & had a weird eye twitch going on. He told her she was just nervous & that she'd be fine. Nothing going on from that email but from the fact that he was emailing w/ her on that account that he didn't use normally and that she was contacting him about being nervous about getting married made me question it. When I asked him about it, he admitted that she had flirted with him at work, he gave her his email & they flirted that way (this was years ago he said). She offered sex he declined. This is what he is telling me. Who knows what really happened & it did really bother me when I found out. I just decided to let it go... I knew about an actual affair & we were working to heal that wound at the time.

SO.... he has clearly made some questionable choices. And apparently he is emailing with the OW rather than texting.

So what should I do if he says nothing after 24 hrs?