I have to preface this with "I don't believe in ghosts", but I recall a time when I wasn't so sure. My wife and I were just married and living in a gorgeous old home near the seacoast. During the few years we lived there I had this recurring nightmare of a "ghost" dragging my wife out of bed and into the kitchen, where she and I tried to fight it off. Pretty disturbing for both of us; I would wake up screaming every time.
Well, anyway, we moved out of that house and I never had it happen again.
Where's Sigmund Freud when you need him? He could explain it.