It's not silly, since Crossdressers, Tranvestites, Transsexuals etc. are all part of the transgendered community.
On this forum I'll bet they'll be several topics along the lines of why we do we crossdress? (e.g. http://www.crossdressers.com/forums/...+we+crossdress ) some of the reason range from: It's a part of who we are to feeling sexy.
The question we should be asking is are we driven subconsciously driven to emulate what our perfect woman who we could spend the rest of our lives with? Since finding the perfect woman is a fools errand, it's not going to happen, so therefore we find a partner who is near perfect and compromise. With crossdressing it's different because you have to live with the otherside of you; the subconscious driving you to reach that perfection.
Since every single one of us dresses in a particular, style, with a particular hair colour etc. so even if we don't admit it we are exactly on the same playing field as transsexuals since in order to crossdress there is a need to be a female in one way or another. It's just that we don't feel that we're a female in the wrong body.