Wow, LS13, I respect you for setting a clear boundary w your W. I too I considering this my boundary, as my H's R w OW is not yet a PA (although I still feel an EA is just as bad or maybe even worse in some ways). I have NOT yet voiced this to my H, b/c part of me is NOT 100% sure about this boundary.
I agree w FY, though, in that you should be ready to follow this through if it should happen.
As you have a 1-year old son, have you considered that your W may be experiencing post-partum depression? A friend of mine went through this & she became a radically different person for a period of time and really wasn't interested in her "mom"role (either). Gradually she came back to herself, but she went through therapy and got on A/D medication. There was no OM.
M- 18 T-21 S-14,11 & 10 BD 6-18-2012 (OW-EA) H moved out 11-3-2012 10-5-13 Me- I want a divorce. I want to move on w my life. 11-25-13 Jointly filed.