I wouldn't lose hope. I think you feel that each and every day will make or break you- it will take MUCH longer than you think you may be able to stand. If you are resolute, you will hang in much longer than you think you are capable today. Know going in that this may take two years to turn around. Get used to that idea. You will not be happily married again in two months, won't happen.
Your wife asked the C if feelings could return. Not sure what the response was from the C, but I can tell you absolutely "YES!", they can. My wife asked the same question. My wife, too, told me that she had been unhappy for years (I think close to 10 if memory serves). Wow, what a gut punch! I had no idea. Like yours, my wife didn't think she'd ever feel "in love" with me again, and wasn't attracted to me. Know that women (a lot of men too) base their attraction for you on their feelings about you- so don't take it that you are ugly, just that she doesn't like you very much right now.
In my case, my wife was in an EA and spoke to the OM daily on the phone, getting all of her emotional needs met. She found him attractive, therefore, I was not. Most women cannot have two men occupy their hearts at once. Is your wife involved with anyone else at this time? If she is, she will never get feelings back for you while she is still speaking to the OM.
You're a fixer? I'm smiling right now, because everyone on here is too! Good news for you- there's plenty of "fixes" you can occupy yourself with. As others have stated, start living like a great husband and father. Don't expect results, though. Those come later. Your wife won't believe any of your changes yet. She's not going to look at years of poor behavior and believe that you've reversed all of it in a few months. Stay steady.
On detachment, don't think it means ignoring your wife. Don't pursue her, crying and begging and trying to win her back. Just BE the man she needs. Let her see, first hand, what shed be giving up if you left. That's the best way to fight for your W, by becoming a better man.
Just so you know, I fought for my M for two very long years. I made tons of mistakes. There were days I sat in my car praying that my wife would have a moment of clarity and return. Some days I thought I had nothing left in me to fight with. I found I could endure much more than I ever gave myself credit for. I won my W and marriage back. My wife is "in love" with me again (whatever that term means to her). She's attracted to me again, and no longer remembers our marriage as unhappy, but as very happy, despite her huge "mistake". As for me, well, I'm never going back to that person that I was that allowed this to happen to my M. I know what complacency can do, and I avoid it like the disease that it is.
Good news for you- there's plenty of "fixes" you can occupy yourself with. As others have stated, start living like a great husband and father. Don't expect results, though. Those come later. Your wife won't believe any of your changes yet. She's not going to look at years of poor behavior and believe that you've reversed all of it in a few months. Stay steady. 