Stephee,
Welcome, it's good to have you here. I am 50 and just came to the MTF realization a month or two ago. I have been experiencing bouts of cross dressing off and on since I was 9. Never did it fully in public. This past January, I started therapy thinking i could move beyond it and not have to tell anyone. I have been married for going on 25 years and 3 teen daughters. After a lot of looking around at info on line, deep soul searching and trying to connect the dots of past history I was surprised that I came to this conclusion but here I am. One of the hardest parts for me was simply remembering. I have a very shoddy memory of anything before 13 or so(even now. I did not remember becoming a member of this site two years ago but had and only rediscovered it this past March). However, the more I delved, more memories came trickling back. Still more like snapshots of someone elses life... I came out to my wife about 3 weeks ago now. That was both an enormous relief and a huge source of tension before hand. I have not come out to my children or many others from there yet. Teen years are so stressful, we were not sure that it was needed yet. Although, through friends and media, they are so trans savvy, I am thinking of doing this.
Just wanted some description so you have a source of reference. I too, did not think "I am a girl" when I was young. I just thought I had some kink that gave me the compulsion to wear women's things.
I cannot tell you what to do. However, I can include some information I received before coming out to my wife. It sounds like you have been struggling with this for both a long(the dressing) and short time(therapy). Great steps but if your wife has not been aware, this may be a huge shock(sometimes it explains a lot to them). Some spouses see it as a betrayal and/or long term lying and feel hurt. Some accept it all to easily and then add it up over the next several days, over and over again. The surprise of showing up dressed or by informing through pictures first is usually not a good choice(can cause surprise, humour and fear off the bat). She may wonder if you are gay. She may wonder what she did to make you this way or what is wrong with you and/or her. Bottom line. She is catching up in a short time and may mentally and emotionally go in a lot of directions. Try to be calm. Try to breathe and be still. Try to think of any question she may ask and answer them before. Sometimes the answer is "I don't know yet". Be there for her. Be ready to answer the same questions over a couple of days. Finally, have a sense of hummour.
Often these journeys are all about the transgender person(and ultimately is) but even if you feel like you are the same person you may no longer be perceived as such. However you choose to progress will effect her and potentially the rest of the family. This may all seem obvious but it is good to keep in mind.
I can tell you that I had been suffering from depression and some other symptoms for a long time. She has wanted me to go to counseling for a few years now. I started by telling her I loved her and wanted to stay with her. I then asked if she would just listen until I was done and would then answer any question she had. I then explained my life long challenge with cross dressing. Maybe a few larger discoveries(not too much info at this point). Then, that I had come to the conclusion that gender wise, I am a female. I asked if she was familiar with the difference of gender ID versus sex. After a short explanation of that, I opened up for questions.
This has been how I was prepared and proceeded. It went very well for us and we are communicating pretty well. I am not entirely sure what my future holds yet. I am pre nearly everything. About to visit for an electrolysis consult, about to meet with my GP about a referral for an endocrinologist. However, this is mostly for information. As I understand it from many on this site, there are many choices about how far to take this journey based on your needs. Let me add this has been a greatly supportive group of people here. They have helped me with a lot. If I or we can be of assistance, ask.
As far as a GP goes. If you have insurance they sometimes have a list available on line through their site. Down side to that is it probably won't have a flashing arrow that says "Trans Friendly". If you pass along your location(as others suggested) there may be info on this site or you may get info from other local members.
Sorry if that is too much information. I hope this all works out for you. It is a bit of a roller coaster ride, from my experience. Take any or none of my suggestions. Just that, suggestions and narrative of what I have experienced.
With loving thoughts,
Joanna