A dream is comprised of multiple feelings associated with whatever the dream 'means' to us... if we are terrified of our dreams it is likely the result of a deeper network of our 'map of the world' our resourceful and not so resourceful beliefs and the in-ability to reconcile them;

So yes in a way you're right, most people wouldn't be able to handle the reality of their dreams coming true, but I'd say that has more to do with their internal world than anything else.

Thanks for getting my brain churning ;)