All of the risks that were present 5 yrs ago are present today. You moved away so that your wife - and you - would not be in close proximity to the OM. Being in close proximity to the OM means that the risk of a resumption of the affair goes way up because her feelings will be triggered. When her feelings are triggered, she will be in a position to resume the affair. You seem to imagine that you are immune from this because it has been 5 years. The fog will come back once she is triggered.

But I also know others have survived and recovered without ever relocating.

I don't. But I do know many others who have resumed affairs because they didn't move.

How to Survive an Affair chapter in HIS NEEDS, HER NEEDS
p. 177

...I have seen husbands build new and wonderful relationships with their wives but then go back to their lovers after five or six years of what appeared to be marital bliss. When I ask them why, they inevitably tell me they miss the woman terribly and still love her. At the same time they stoutly affirm they love their wives dearly and would not think of leaving them.

I believe a man like this has told the truth. He is hopelessly entangled and needs all the help possible to be kept away from his lover and stay faithful to his wife. I often recommend that a man once involved in an affair come in to see me every three to six months on an indefinite basis, just to talk about how things are going and to let me know how successfully he has stayed away from his lover. He must resign himself to a lifetime without her. He must certainly not work with his former lover and should probably live in some other city or state. Even with those restrictions the desire for her company persists...

"It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena.." Theodore Roosevelt

Exposure 101