It seems like you are being a fine friend, and there is little you really need to figure out. Your friend is changing, yet remaining exactly the same.
From my experience, the friends who remained with me through my transition are given lots of room to "mess up". They knew me with a different name, a different body, and in some ways a different life. The challenge for me was integrating the past and the lies and even the shame with who I was and who was becoming.
For my friends, this was sometimes hard and often confusing. It didn't help that for the first couple years I was a total wreck as my body adjusted to the hormones and I began to be solidly treated as a women (not as much fun all the time as one may suspect). They related to me as "a buddy" sharing the things that buds share, even if they understood me to be a gay guy, I was still a pal. Finding that balance was hard for them.
Guys relate to each other differently than they do to women. You and your friend will just need to figure out how (if at all) your friendship will change. There is not correct answer, except the one you both decide. The one that allows you to be close and share things with the other.
You can look at it has having the actual "best of both worlds". You have a friend who "gets you" as a guy, but also understands you though the eyes of a woman. What safer way to find out if you putting out the wrong messages to potential dates?
