Parents like this is the sole reason as to why kids move out whenever they can and never go back, and basically keep minimal contact with them after a while. It's a sad thing really. Parents can be just as foolish and immature as kids can at times like this, where they feel like they're losing control... They need to learn to get over the fact you're no longer a kid and treat you as an equal.
Many parents never do this, and many parents have lost the friendship of their children forever coz of it.
Sad, just sad.