He is still in his crisis. That stress and the not feeling good is partly that and partly a middle aged guy thing. Have you been through menopause yet? He is having the same symptoms! It is not fun. At least not for some people. One other thing, even if there is a OW he is making a move back to you, that is good no matter what. Could you be hurt again? Absolutely. However no risk, no gain. In order to make it though this crisis you must be willing to risk everything in order to succeed. I think you are correct that some of this trip might sound better than it is. Lots of things in life sound that way. RL(real life) gets in the way all the time.
If there is an OW maybe he is looking for a safe landing spot(you) before he dumps her. Like I said before you will know eventually, just continue to have patience.
In a lot of ways this part of the crisis is much harder than replay. It is different, for sure.