It is unfortunate that there is no magic crystal ball to tell each of us what the right course of action is. I will offer my observations and experience for what they are worth.
I have read all of your postings. I sense, or maybe feel, a fairly consistent undercurrent in each of them. What I sense is that there is a part of you that still loves your wife. And a part of you that, if you are truly honest with yourself, wants to remain married to her. At the same time there is that other part of you. The part that still, after 5 years, can't believe she did what she did. The part that still holds a lot of anger and pain. The part that cries out for justice and whispers to you that you are stupid if you let her "get away with it" (maybe that's the pride you speak of).
I sense that those two parts of you constantly battle each other for supremacy; for victory. And that is why you feel so tired; defeated in a way. You just want the battle to quit. One side to win.
I suspect most of us have all felt that way to one extent or another. Some grow exhausted much more quickly than 5 years and throw in the towel one direction or the other. Some struggle most of their lives and never make a conscious decision (which becomes a decision to stay by default)
Staying by default is just ongoing misery so it is good that you want to make a decision. It appears to me, though, that you don't truly know what you want it to be.
In my past I experienced the internal battle. Mine was when young kids were still at home. They trumped the inner voice urging that I obtain justice by dumping her. You don't have that to factor in which I am sure gives the "justice" voice more power.
I understand your exhaustion and I do think you need a decision of some sort to move ahead. What I suggest it that it doesn't have to yet be an "all or nothing" decision. It doesn't yet have to be "commit to R" or "commit to D".
Consider separating (and not in house; a true physical separation) for somewhere in the 3 to 6 month range. The point being to see if there are still feelings there sufficient to convince each of you to give it another honest try. Or not.
And I suggest that if you do that you each commit to No Dating during that time. You need to determine how much, or how little, you miss her presence. Whether there is, or is not, still a feeling of need for her. You would not be able to figure that out if you are dating. The mental, brain chemical, thrill, or whatever ther proper term is, brought on by being with someone new would block any honest evaluation of your feelings toward your W. By the end of the separation period you should have a clear enough evaluation of where you brain and heart are to feel more confident of the D or R decision rather than the I'm so exhausted I have to do something so I guess I will choose option 2 status that you seem to be in now.
I will tell you my truth as I sit here at midnight on a Friday typing this. I have felt that exhaustion. More than once. And I have heard those inner voices screaming at me that I really am only cared about because of the lifestyle I provide and that I should still get justice and etc etc. And I know you wonder if she is still with you for lifestyle only; so her life isn't blown up.
I will just offer these thoughts. Our wives have been liars. Very good at it too. But even good liars can't deceive forever. I know by now that my W does love me. It sounds like yours does love you. And I think you know that. So what you have to find out is whether you still care about her and need her enough to start working towards letting the past go enough (no, it will never just go away entirely) that a true R can occur.
It took time for me to reach that conclusion. And while I reached it without a separation, recent times have given me clarity that it was a correct decision. Last summer and this summer my W has lived in a vacation house we bought on the west coast ( home base is the Midwest) and I go there a little each month as my work schedule permits. Those weeks of separation at a time have shown me that there is still love and need. On both of our parts.
And thus my suggestion that a physical separation for a few months should give you the clarity you need to know, for sure, which way to go.
Whatever you do, I hope you find peace.