I had a happy childhood and so did (as far as I could tell) the other Witness kids I knew.
These kinds of things depend on much more that just the religion you belong to.
To blame your "miserable" childhoods on just the religion is wrong. I don't buy it.
What your parents were like is probably more important than the religion. Strict, moderate or soft – it makes a big difference, even for non-religious families.
Strict + Religious, now that's asking for trouble.
For me, my Dad was moderate (most dads are, imo) and as for my mother, well, I could of (probably) got away with murder.
"Fathers, do not exasperate your children, that they may not lose heart...."
My advice to some of you here, is instead of wallowing in self-pity, take a few moments to think about the millions of children in the world who really do have dreadful childhoods - many who, for various reasons, will never make it to teenage years let alone adulthood.
Mike.