One thing I've seen a lot expressed by the wives who will come to various support forums in shock after finding out is that there's a real mourning/grieving process. The life they thought they had is falling out from underneath them. They had a certain image in their head of the person they married, and suddenly that bedrock in their lives seems completely alien. Spouses, especially those who've lived out most of their adult lives in that marriage, have their own totally different but equally painful suffering from gender dysphoria. You've had decades to come to terms with this, find coping mechanisms (however unhealthy or unsustainable), and generally wrap your head around your dysphoria. She has not. What seems like hot and cold waffling on her part is likely her speeding through the stages of grief over the loss of the life she thought she was going to have, and of that image of you in her head.
Marriage counseling is always a good idea when times are hard and I'd always encourage it to anyone struggling, but I would also suggest both of you talk to that therapist individually as well to help each of you with the pain you're going through.
I'm sorry you're going through this. Having that path seem to open up, then shut right away is heartbreaking. I really hope both of you find happiness, whatever that means and however it looks for each of you!
