After the first time trying it all I could think about was doing it again. I remember walking home with my friend who was doing it for first time and both of us agreed it was the best thing we'd ever done. We did it again shortly after.
I've done MDMA and other hallucinogens a lot and quite enjoyed then. I guess, for me, there is always the knowledge that it's not real. No judgment at all, though. Chemical balance is extremely personal.
It's kind of like going to a movie or a concert that I enjoy, but at the end it's nice to return. If the high continued I'd feel miserably unhappy despite the artificial chemical boost.
That makes sense, but GP wrote "once you've done it, everything becomes dull without it". I interpreted that to mean it happened after the first time.