As they say, each MLC and its sitch have their own flavor. Because your wife has only mentioned D a few times in 2.5 years, and there appears to be no OM, then I would continue to wait for as long as it took. Not filing D tells me she continues to be undecided / confused about both her past and future. Even though she sounds angry, my bet it is mostly directed within her and she is severely depressed.
Mine's a bit different. 1) she did file for divorce - hired one of the meanest firms in town. 2) there is OM, and although they do not live together, she admits to a family counselor they are in a R. 3) although she temporarily called off the D to sort out our investments, she plans to refile once this is done in 8 to 12 months. She is happy because she is own her own for the first time in her life, she continues to be infatuated with the attention from OM, and she is getting a good spousal support which should allow her not to work for many years. Combined with splitting our investment income, her working part time, and spousal support, she should gross between $8k and $9k per month. So you see, I've got no financial leverage her.
Given the preceding, I will only stand for roughly say, 8 to 15 more months, or until the D is final. Then I must move on. It would be unhealthy otherwise, and really, I know there is more life to be lived out there and I don't want to miss anymore than I will over the next year. If she "Awakens" one day after the D and wants to talk about a reconciliation, and I'm still available and of like mind, my reaction today would be to say let's take it slow and see where we go. Better chance is that she moves on, and then, so must I. I will be 50 in two months. Life is too short. I can't see dragging this out for years after the D is finalized and she's moved on. That's my reality. Makes me sad, but I've got to buck up and accept it.