I think no matter how it is handled before coming out as transgender, it has in some way been a burden on the relationship. When you let that burden down, you may feel relief, but remember, your wife is still is still holding on to their part of the burden. Let the burden down as gently as you can, and provide support to them so they can do the same.
That no matter how your spouse handles the news initially, they can be a super-trooper rock-star about it, but at some point it will sink in that they have lost their husband, and there is no doubt that they have. They signed up for Prince Charming, not Princess Charming. All I can say is be patient and let them know in no uncertain terms that although they have lost a husband, they have gained a much better person who still loves them.