Over on Reddit someone asked about a sadness they've started feeling when crossdressing. Amy's comment hit home, and I had this to say:
If I had to guess, I'd also say dysphoria.
For me, 'cross'dressing was always a bit of a double-edged sword. Most of the time it was great, especially when I was younger and just figuring things out. But sometimes, and especially more-so as I got older, there was the side of it that made me feel terrible. Part of it was as Amy_of_Dallas says, that the clothes don't hang quite right, etc. But mix in with that the feeling of being a fraud, the suspicion that maybe I wasn't a woman, or when every moment of enjoyment is tainted by the knowledge of that impending crash in a few hours when you'll have to change back before [whatever], then the feeling that I'd never be able to be what I wanted, that the closer to it I got the further it was just out of reach, the shame and grief of daring to be a human being, of daring to be happy.
In the beginning, 'cross'dressing was great. It was my little secret, my playtime. I could lounge around and read books or play games and for once just be. But by the end, it was something I loathed; something I'd try to hide, even from myself, lest I be drawn in once more and for those few brief moments of solace pay in weeks of lament.
That was a big part of what pushed me over the edge in the end. That I could not escape this "addiction" after years and years, and yet that it brought nothing but sorrow. Now of course (or, I suppose, I shouldn't say "of course") things are much better. As soon as I made the decision to transition and started taking steps on that path, this angst cleared away. But then, now it's become daily wear. It's just clothes. I suppose it always was. But now there is no denial, no knowledge of the impending crash, no secrecy nor shame, no fearing to never become what I always knew myself to be.
Besides, the clothes fit a hell of a lot better now ;)