It's a hard question to answer. I tried on a pair of pantyhose when I was 12, and I never looked back. It's like it was something that was already inside of me waiting to come out. I found that I enjoyed wearing skirts and dresses, and enjoyed the entire female presentation so much, I wished I'd been born female to begin with. Now such things seem normal to me, and I couldn't imagine not crossdressing. Once my wife asked me this same question, and I really didn't have any kind of simple answer to give her. Like Karren said early on in this thread, I'm driven to do this, and in its way, like with many things, it helps to complete me. Is it a manifestation of the person inside of me? Yes, partly, but not entirely. Do I wish I was a woman instead? Yes, but if I was, I probably wouldn't love wearing skirts and dresses nearly as much as I do now. I don't hate being male enough to use it as a complete answer for this. It's not an alter-ego thing, because I'm the same me no matter how I'm dressed. Is it because I like it and I enjoy it? Well, yes, but there's more to it than just that. I enjoy a lot of things that don't bring me to the point of obsession. I do it because I must, I guess. It helps complete me.