Well, I would personally define it as medical transition vs, just not transitioning. Basically taking any steps at all in the way of: HRT (full dose, or long time period), surgeries, and living full time in any way, would be transitioning to me (or transitioned, in the case of those who did whatever parts they needed to and ended up where they needed to be, even if they're no longer taking HRT for example).
I think the type of support that people who have chosen not to transition is different. So much of the support is directly related to things such as: passing, how to get on hormones, changes once on hormones, questions on surgeries, how to go about planning for surgeries, etc. etc. If you say you're not going for any of that, people seem to just shrug their shoulders and either say they can't understand it or have no input.
Like I said, I understand it's not the majority, but I often wonder how many other non-transitioning trans people there are out there who are silently suffering, never seek out a site like this, or if they do, they don't really encounter any form of help specific to their situation. The whole reason why I came to this site in the first place was to try to find other people I can relate to. There's been a couple, and we've mostly discussed various thing via pm. There really isn't much open discussion of people who have chosen to not transition, yet are still trans.