My dilemma? Is my fiance right to make these demands or do I have to take a stand?

Hello all, it's been awhile but i'm back because i'm having a dilemma. My fiance has always been insecure of my relationship with my best friend, and part of that is due to the fact that my best friend is a guy. He and I have known each other for about 10 years. The problem is, my fiance feels that there is more than friendship to our relationship. The truth is, there is NOTHING more than friendship there, but we are just really close; if he were a woman no one would think twice about it. We see each other regularly; talk or text on the phone daily; and are always arguing and making up. Lol I would call our relationship dysfunctional, but it works for us. In addition to that, we do tell each other "I love you" occasionally when getting off the phone, and at times, I spend the night at his house when i'm in his town visiting. We really grew this close when he had to deploy to Iraq a few years back and it's been that way every since. My fiance does not want to be anywhere near my friend, and has refused to allow him to be a part of our wedding, even though he knows how much it means to me. I'm not even sure he will allow him to come to the wedding. He also gets angry whenever I go anywhere with my friend, and when I invite him along, he refuses to go and I end up just canceling altogether to keep the peace. I have no idea what to do. I love my fiance to death, but I also love my friend and he's stuck with me through thick and thin. My fiance is demanding that I distance myself from him, and it may very well cause a rift in our friendship. I do not know what to do, and I don't want to lose either of them. I understand my fiance's point of view, but he has several female friends with whom he is close with, and I don't have this reaction. What should I do? If I have to end my relationship with my friend, then exactly what kind of friend does that make me?