Being away from someone definitely makes your wanting of them stronger the next time you see them. But if you go long enough without talking or seeing someone, your feelings tend to diminish. Your mind stops thinking about them as much. You begin to forget them and forget how you felt about them. The heart lets go after a while.

I'm saying this from the point of view of someone who hasn't found anybody special. If this person is like, your soul mate.. maybe it's a different story.