Agreeing with washiz here:
He is playing you while his partner is sitting by & cracking up.
A man his age knows all too well how naive you are. Definitely a game...entertainment purposes only. How long can I string her along, and how much crap will she eat?
When you kept going along for the ride instead of calling him on how ridiculous his overtures were, that's when he realized he'd created a monster.
How, then, to stop? Easy. Ignore you...blow you off. You meant nothing to him then, you mean nothing to him now. Besides, what are you going to do about it? There are no social or professional consequences for him doing what he did to you.
I realize you're only 21, but can I ask what version of reality you were operating under...was this the me version, or vista?
I'm also wondering what's going on with you and your father...something is up with that relationship. I'm guessing you're parents are divorced, or your father is otherwise out of the picture.
Sorry for your pain, but hopefully you learned a great lesson.
Oh, and one last thing: If a guy pulls up next to you in a van asking you to help him find his lost puppy, don't get in.