You might not agree with me but sir you got slapped in the face twice when coming to your wife as a loving husband should in her time of need.
regroup? - you need to take some serious time away from this person. and Re-evaluate and concentrate on yourself as a individual not as a person in a functional unit of marriage.
Know Yourself.
I see here, the situation that you are codependent on your wife, your wife is codependent on another man. Sooner or later everyone is going to get sick and tired of eachother. Will this work out to your benefit? Depends on how well you know yourself and understand yourself as a individual when reconcillation is possible.
But for right now, she is shacked up with another guy. And you need to develop the confidence in yourself to have said "No, you are my wife. I dont feel confortable leaving this room." Immediately rather leaving an coming back, twice. You fell subordinate to some ahole stealing your wife. No More of this behavior.
Your anger and coldness is understandable, but as long as you harbor those negative emotions positive growth for yourself will be stunted or not be able to occur. I think it is important to go back to your initial post and question, "The blankness and zero responses from my wife are the hardest blows, how to avoid them please...." as this is really what you need for yourself right now.
Leave her alone and let her come wandering after.
No more phone calls, no more texting, no more family time. let her realize what she lost. something is amuck in fantasyland. why was she in the hospital? did OM say he was taking a break, leaving and she had a nervous breakdown? that behavior doesnt last in fantasy land, fantasy land is all about be happy and funny and sneaky. one or two more episodes of co-dependence and he will start questioning if everything she told him about you was really true and how flaked out she really is. have you ever seen this situation before?
Use the time that she starts to bring the demise of her affair as time to develop yourself as an individual without her. You may even begin to see her differently.