So, my best friend is a guy. though he is very sweet, and nice to me... and extremely hot... he seem's to like me more then what we are. That's not the problem though, for I beleive we both could live with that. Any how the problem is that he get's overly protective of me. If I talk to another guy, and he find's out he will be like "I knew you first!" or "So what your just going to find a new best friend?". And you know this upsets me, because I know he knew me first, and yes im looking for new friends, but he will always be my best friend! I don't want to say anything, because he takes this to seriously and gets upset. And when he's mad he acts stupid!
I love him, i really do! And he know's I would do anything for him... but sometimes it seems like he's doing it on porpose... so he can have me all to himself.
We never used to be like that.

Im not going to ditch him for new people, but I dont want to have one friend, and no boyfriend for all of my life!!

any advice as to what I should do?

i don't know much about this kind of thing. but i would say that you should really talk to him once about this whole issue, being completely open and honest. that's got to be harder than it sounds, but really the only thing that can clear up the confusion and emotions.

Bleh. Certainly don't take him as a boyfriend, because his behavior would only worsen.

He needs to back off. There is plenty of you to go around and the friendship will not crumble because you talked to someone else. Tell him he needs to cool his jets, that you feel held down by his behavior, and that that's not how friendships work. Tell him just because you make new friends you don't value your friendship with him any less.

Just TELL him that. Explain to him he's always your favourite etc.