First off congrats on the appt. I am just 3 months on T so I too remember the beginning, I am not sure it is something we will ever forget. I too have a wonderful woman in my life who has identified as a lesbian for all of her adult life, so this is very new and different for her as well. She is extremely supportive, our bodies are just a vessel what really counts is what is in our hearts, mind, and soul. We did talk a lot about the transition, but now we try to not overwhelm our conversations too much with the transition, we have trans free time and just be sure to take the time to continue to concentrate on the other aspects of our relationship.
The changes that I have noticed for me have all be really positive, some may be because of the T itself but some are due to the changes that I see happening to my body and feeling like finally my body is getting in line with the rest of me. Also starting to see glimpses into what my future holds for me is exciting. I am much calmer, there is a peace inside of me that I have never experienced before. My sex drive has increased a lot, and I do find that I don't feel the need to talk about my emotions as much as I used to. I am much more energetic and happy.
Good luck with your appt. for all of us the journey is individual, we all walk it in our own way at our own pace.