I feel that I am aware enough to put up a psychic shield when I need to.  In fact, I can regulate it pretty well.  Many people who are extremely unfocused or cannot do so it is a simple matter of understanding what you have and what you can do.  More over, many people are in the new line of sensitivity and it can be a hassle to be sensitive to everything.  Put  up the shield and you will encounter less energy vampires.