Just remember, the last time he opened up to you about something to do with OW and work you freaked out on him. That'll be fresh in his mind, even if he's just visiting the other office on a work trip.
Me: 31, W: 29 T: 4 M: 2 Kids: 3 (SS: 7, SD: 4, D: 3) Separated, still living together: Nov 2013 Separate bedrooms: Feb 2014 W working away; kids with me: Nov 2014
