Is it a Disney curse - Is that why these girls (and some guys) are going nuts?

No, it's not just Disney, it's pretty much what can happen with child stars when there is too much fame and fortune too fast.

Some parents manage to keep children grounded, others don't.

I think it's more likely something common to many young people who become well-known at an early age. They never get to be kids, and they're not old enough to have the judgement to know when they're being used. Add in the fact that they have parent(s) who push them in front of the cameras for money or for the vicarious thrills, and you have a recipe for a really effed-up kid.

Anybody who thinks that the Disney studios are any different from any other studio in town as far as exploiting people for every penny they can is kidding themselves.

When they are on Disney they have to be perfect role models. No mistakes, no teenage parties, no going out with your friends and doing normal stuff. When they break free of Disney they are being the teenagers that they missed out being when it was their time.

No that's what happens when your in the spotlight for too long and Disney fans except you to be this perfect role model !