BC39, The shower conversation that you had with your wife feels EXACTLY like one that I had with my wife (in the shower too I might add!!!!) while going through her EA. At the time, she was swearing to me that the OM was long gone and totally out of the picture. It "wasn't him", and she was "trying" to get her feelings back for me, and it "wasn't working" and made her feel discouraged.
I've already told you what I wish I had dug harder for at the time- she had been in contact with the OM. The lack of emotion that your wife is displaying played out in my house too. What I came to learn is that some WAS spend an enormous amount of energy pushing their feelings down around the S - lest anything about the OM pop out. They save their feelings for the OP, not the spouse.
I don't want to send you off in a panic, but I would be looking like crazy for evidence that the A has restarted. It's like dealing with a drug addict- they can be normal off the substance, but then fog right back up after getting another taste. It seems to me that she is deciding between the two of you. Heck, it may even be a different OM, but probably not.
We like to go through our lives with the notion that we are unique and different, but since going through this, and reading all of the posts - it turns out we all play the same script! It's crazy! We could have swapped places in the past and you would have sworn that my wife's words were your wife's!
My sister was involved with another man (we don't speak) who kept a separate phone in his car that he would only pull out during the day to call my sister. Cheaters are crafty. You have to think like a cheater to find the evidence. It took me a long time with my wife- she had become VERY careful. I mostly believed her when she told me they hadn't had contact, but I would search anyway. For months I searched. Then one day she got sloppy...... BTW, that still didn't end it....she got craftier still.......
Do not tell her of your suspicions- if it is true then it is essential that you let her get complacent, or else she won't slip. Additionally, if it's not true, she never has to know that you checked. Trust but verify!
It's just my opinion, but your wife's words are so much like the ones that my wife spoke that it's scary. Keep being the man of her dreams, (do not profess unconditional love though) all while keeping your eyes open. I'm not at home with you, but I smell another rooster in the hen house. I hope I'm wrong.