I don't think it's accurate to analyze the membership patterns and come to a statistical conclusion to that question. There are too many variables that can be assigned to why someone would not be a die hard, everyday poster here.
While a lot of us share a somewhat common past when it comes to crossdressing, we are also all unique in our own ways. I'm sure there are some who have packed up their girly things and never looked back. I'm also sure there are ppl here who cringe at the thought of never dressing again. I think as human beings, we all need answers about why things happen. We need to know why things happen. Especially when we are taught that certain things go against what we perceive as "normal" I know I do. I spent a long time trying to figure out what was going on with my life in order to make sense of things.
