I'm hesitating to post this...SOOOO... What if you restrict supply because you have a monopoly? So that demand never drops?
You know... Like how they do with diamonds. And gold. And oil. And... And...
Demand and Supply have nothing to do with each other. Its where the curves intersect that determines the market price.
For example, if in a given market Supply decreases and Demand stays the same the Supply curve shifts to the left along an unchanged Demand curve, increasing the market price. If you through a moving Demand curve into the mix things can change even more.
Sorry for the Econ lecture, I just couldn't help myself.