It isn't about a wife being supportive... transition isn't like learning to play a violin or something... you are messing with the fundamental aspects of attraction.
Really, think if the situation was reversed? What if you were with a man and he suddenly told you he wanted to be a woman? That his muscles would go away, his hair would go away, his behaviour would become more feminine and he would dress more girly...he might even cut off his thing and his sexuality would drastically change.... I would go "good luck with that, but I want a man" and end it.
I'm attracted to men. I like the muscles and all the male features. If my partner wanted to get rid of all that.. I wouldn't be attracted to him anymore. It is completely reasonable.
So, if I were in your place...and my wife said "sorry, I'm just not into it"... I would accept it and allow both of us to move on with our lives. Trying to "work things out" with counseling and stuff is like trying to turn a straight person gay. Sure, you could go "maybe you could get used to it? Want to try?"... but if she really isn't interested and knows she wants a man... you really need to respect it and move ahead with your life.
Instead, by trying to stay together, she will continue to try and hold back your transition as best she can. The more she can stop you from doing fem stuff, the better it is for her. She will try to stop you from growing your hair, growing your nails, wearing makeup, wearing clothes, changing your voice.... every step you try to make will be met with resistance (and it will make transitioning just that much harder as you keep trying to hold onto her...and move to what you want to be... ).
I have a trans friend who is going through the same thing. Constant ups and downs with her wife. Constant battles over what and how much she can do. No surgery allowed, no dressing allowed, no coming out at work allowed.....
So... my suggestion...is to say "ok" and make plans on how you can move forward. End it in good terms.. try to be friends... but, in the end, you just aren't her type anymore...