Most Helpful Girl
For all human kind has discovered about the world, scientists have yet to explain the nature of many bodily functions that, due to their normalcy, we take for granted. Why do we cry, why do we laugh, why do we get goosebumps when we're cold? Why do we die when we do not sleep? And why do we dream?
The most common theory is that, through REM sleep, our brains enter a state of repair in order to "digest" and sort through our day; the product of said digestion is the regurgitation of subconscious manifestations know as dreams.
The emphasis is on "subconscious" - that the subconscious mind comes alive when your conscious brain is asleep. There is tons of literature and sites on dream analysis and interpretation, if you're interested.
I'm in the same boat as you, though much farther up the bend. It's been 9 years and he's still pops up in my dreams. The last time this happened a few months ago, I even told him, "You've GOT to be kidding me! Whaaaaat the hell are you STILL doing here?" lol! Seriously, enough is enough! Too bad my "subconscious self" never matured past my teens? Hopefully it's not that long for you. :D