You are who you are.
In my opinion, what you choose to disclose to someone is whatever you feel is appropriate at the time.
Medical conditions are, for the most part, a personal and private affair. Let's consider this - how many people have you met on a social basis told you any of these things the first time you met them (unless you're at a support group)?
- schizophrenia
- bipolar
- heart surgery/transplant
- appendix removed
To me, if we consider GID a medical condition, not an illness of the mind, then it's personal medical problem that you've addressed. The only people that need to know then would be your health care providers, and any romantic interests.
I could say more, but I'm afraid of offending people. =)
Edit: Oh, my answer to the question neighbour/neighbor. Queen's English please - neighbour!