She could have gone elsewhere but she didn't
Is this because she didn't have the opportunity, or for some other reason? That's one thing to unscramble.
I had an affair for all kinds of complicated reasons. My marriage had been over for a very, very long time before I had an affair, though. By the time I had got to the affair stage, I had long since wished fervently that my XH would have an affair, just to give him something to think about apart from himself.
But that's how a toxic marriage works.
One thing I do know, having had a previous affair, is that being found out tends to jerk you into feeling something along the lines of "OMG, I just want everything to go back to normal, and as quickly as possible, or I just won't be able to cope with all the emotional fallout, and might as well be dead".
In reality, though, if you are going to work through an affair, it is a very, very long road. You would have to unscramble why it happened, and what part you and your wife played in it. Would she have had an affair, had the opportunity have arisen? There's an awful lot to work through. If you really do want it to work, as opposed to having a knee-jerk reaction which makes you want to re-establish the status quo asap, I think you might both need to involve a counsellor. Everything you say about your wife being perfect, ideal etc means she's on a pedestal which no ordinary woman could ever live up to - or that you are idealising her because of what has happened. Neither is conducive to a good relationship.
You would also have to be open to the idea that you might both be better off apart.