Hey Kelly....just wanted to say I'm sorry for what you went through when you were younger. But it sounds like you have a good handle on things in your mind and life. Good for you for telling your wife. I am by no means an expert, but all I can suggest is being open and honest and letting her do the same about how you both feel about the past, and about the present crossdressing. If there is no issue from her side of it, I see nothing wrong with it. If she does have a problem reconciling it in her mind, maybe you guys could go to counceling together if you both felt comfortable with it so that she can learn more about it and maybe why you do it. Learn how to come to terms with it and continue on being a happily married couple. (forgive me if I misunderstood, but I am assuming she didn't know about the crossdressing before you wrote the letter)
I wish you two all the luck.