Hiyas, how far you go with this is entirely up to you. How far were you planning on going? If cross-dressing is as far as you need to go to feel good, then why not stop there? Your wife seems to be ok with that much. If you need hrt or other things, things could get complicated between the two of you. I'm not in a relationship myself but judging from other people's experiences I've read here, a lot of marriages don't last, unfortunately. I'm not saying yours won't, just saying that there's a chance it might not.
I see that you are looking for a therapist, I think that is a good place to start. I just started seeing one myself, and yes it is scary thinking about it, but when we actually started talking about things, it wasn't so bad. I found it feels a lot better talking about things with someone else instead of just bottling everything up or trying figure everything out by myself.Try calling them when they are closed and leave a message perhaps so that they can call you back if that is easier for you. I definitely think you should talk to one and tell them everything and see what you decide to do afterwards. If you decide to go forward, eventually you will have to have a talk with your wife. See what she thinks about this, what she says, what she's ok with, etc, and then decide or compromise. Maybe she'll be ok with this and everything, maybe she won't, but you won't know unless u ask. Hope this helps. Good luck,
-Kelly