I was 18 when I moved out. It was hard especially for my Mother because we are such a close family. I too have had feelings like yours and they are natural. You have a desire to leave to "nest" just like most other late teen early 20's individuals.

Your parents are probably attached because they love you. They want to make decisions for you to make sure you have a great life. They are going to miss you and will probably be scared and worried because YOU have to make the choices.

Prove to them you are strong and you can make it. They will be proud.