If you deny yourself for so long, you are in for a psychological crack, a nervous breakdown.
If you love science, how long can you sit there while a brother at the hall comments that evolution is a false teaching? That he doesn't know where all those dinosaur bones came from?
If you love art and beauty and expression, how long can you sit there without expressing yourself? You think nudes and violence and bad language are wrong? At least they're honest.
If you love someone you're told you can't love, what can you do about it?
If you're told to put off everything and keep your head in the future, how can you ever be present here and now?
If your psyche is a piece of embroidery, and everything you deny is on the underside (your Shadow in Jungian psychology), I'd really hate to see the chaotic mess that lies beneath that of a long time Witness.
Now, to be fair, we do have to deny ourselves. We live in a world of consequences and we have to act appropriately. But a religion that demands you sacrifice so much of yourself is not at all necessary.