Try plain milk before bed instead of chocolate milk, or just a glass of water. Vitamin B6 also sometimes messes up your dreams if you have too much of that late at night. I generally don't eat/drink anything but water within two hours before bedtime.
Realize some things you just have to cope with as long as you live with your parents, but that hopefully won't be forever.
Block the stalker as much as possible and do not respond to him/her. If he/she escalates to the point where you should call the police, then do that, and get a restraining order.