Were you faithful? Have you always told her the truth and been honest with her?

Just a reminder. Christian women don't act like that. That is not even the characteristic of a Christian woman, though they may claim to be. This woman is very manipulative and maybe a narcissist. Time to get away IF you are being controlled. To protect yourself, but you both must sit down and talk it out and see what needs working on.

Why assume the guilty party is a woman?
If your wife cheated on you, then address the fact.

If you want her to stop, and she won't stop or change, then you are only teaching her that cheating is ok. It might be time you walked away from this relationship, and actually it's not a relationship if you are the only one still in love, and real love doesn't allow us to hurt ourselves by allowing cheating to continue.

If you can’t accept her on her terms, then move on. Why try to use her past as your issue for 5 years?

It takes two to sustain a relationship, and trust (imho) is the most important thing. When people are able to pick up and keep going after an infidelity it’s generally because they’ve found a possibility of rebuilding that trust. A lot of times that even takes counseling. So in a situation where the person who cheated isn’t even willing to answer questions, they’re clearly not concerned about regaining their partner’s trust. If the why isn’t discussed, what’s to stop it from happening again ? That’s a doomed relationship.