When I transitioned I figured I would lay all of my cards on the table and see where I landed. No matter what was said, I was going to transition, with or without therapy, with or without letters. Nothing was going to change that. That being said it's not like I didn't have some baggage that was worth taking care of, so I let it all out. Truthfully I am glad I did. It helped me sort out the things that were holding me back from the things that would propel me forward. For me honesty was the best policy.
I personally don't believe that it's a therapist's job to determine who is or isn't trans. That's the patients job. Our jobs are to say what we intend to do about it once we say that we are. For me that meant a full transition to full time living and eventually surgery. For you it could be just the simple act of saying it, to the whole banana, that's your choice.
For me the transition experience enabled me to kick the skeletons out of my closet and get a fresh start in life. It worked brilliantly.