How to cope with liking your best friend when he is gay/bi, I'm a female

Alright so, here is the low down. I have a best friend whom I met this year in college, and we talk about everything. We view communication as very important to our friendship and we are very close.
Well, about a month into knowing each other, stuff kind of happened, and we ended up having sexual relations. We have been having sex since probably, late September. We were basically a couple without being exclusive. We have done basically everything, because we trusted each other very much. We cuddle, kiss, hold hands in public, etc.
Because of my promiscuous past, I saw him as basically just another hookup, because I was notorious for hooking up. I took his virginity, and he didn't seem to mind.
About two months ago, he got used by a guy (let's call him Mark) that he liked and it was the first time either of us did something with someone else other than each other.
I realized that night I liked him by the way I reacted when I found out.
Well things past, and we continued to do stuff. I knew it was wrong, because I knew it wasn't right for me to like him.
Since communication is so important to us, last Saturday night I told him I liked him. I knew it wouldn't end up the way I wanted, but I thought it would be better to get it off my chest.
Well, he basically told me he was alright with me he liking him, and told me he liked Mark and wanted to ask him out, because he forgave Mark. Well we talked and I told him it was a bad idea, because we know from a friend that Mark is not a good guy for relationships. So that was said and done, I was a little cheesed off, but I think you can understand why. He is bisexual, but prefers men, and he has never dated a boy.
We were having a casual conversation about V-secs yesterday and he told me he should get one so he doesn't get anyone pregnant on accident. I told him he wouldn't because he would never be with girls, since he liked guys so much more (we joke around a lot), and he told me he does plan on being with some, just not right now, and that he wanted a boyfriend.
So, later on yesterday after I left, he told me he had a boyfriend, which was a friend of his back home (we live in college, and our homes are actually only about 15 minutes away from each other). Let's call this boy Gus. Now, Gus is 17 while my friend is 20. Gus will be going to a college 5 hours away next year. But I am happy he chose a guy he is friends with.
The only thing that really bothers me is that he basically kept jumping from people to people just because they were males! Also, him and Gus HARDLY talk, and my friend has been notorious for in his thoughts for just wanting a boy.

I'm not against him being bi, but I think some people can sympathize with why I am upset. He basically told me that he liked me, but he wanted a boyfriend. He used to tell me that gender really never mattered, so I think that is why I am a bit salty about the situation. I don't want to sit here and be mad, because I want to be happy for him.
I really like him, because he's really one of the only nice guys I have ever been with. We see each other all the time and it's kind of hard to just get over it, because we are best friends, we hangout everyday and it's basically unavoidable.
I also feel like things between us will change, but he said they won't. He said we will still have sleep overs, etc, just no kissing/sexual interactions. I guess I am not just jealous because I like him, but because I'm just afraid of losing him as my best friend, even though his boyfriend lives nowhere around here, so it's not like he'll be taking any of our hangout time.

I would just like some advice on how to cope with this upset feeling that he won't date me because I'm not a boy and help me get over him, because I will not wait until he wants to date a girl, I'm not about to be put on the back burner.

Sorry that was so long, I feel like every situation is unique and I did not want anything left unsaid. If you have any questions, don't be afraid to ask!

it's like questioning why you can't date a horse

I don't really understand how beastiality is relevant, but alright. He is BISEXUAL. And we have sexual relations already. And most the time, he initiates it. And says he likes it.

what do you want from him then?

You said that at the beginning you were just using him. That is probably not the best beginning for a relationship. And his going from guy to guy... how is that different from your hooking up?
Forget the gender factor. You are upset because he wants to be in a relationship with someone else but still be with you. Cut him off and let him know that you like him too much to be less than either platonic friends or a gf.

Good luck.

Your story is funny to me because I can relate, however I am the guy who is bi and I have the best friend who at one time was in love with me and has since moved on. We're still best of best of friends (thankfully) but I regret turning her down when the time presented itself. I was young, it was in college, and we were intimate and living together at the same time as best friends. It's been years since then, but we've had to discuss the situation several times. For the guy, being bi...he may not know what he wants or he may figure that you will be there when he is ready so why not play the field? That may sound harsh but we're guys and if he likes men better than women, you've already lost.

Now, while I still like men, I am also in love with her and she is happily (most of the time) committed to her significant other which I am also friends with. It's hard. There are many other factors that go into this, and it is one big dysfunctional relationship that I love oh so much. However, you are definitely correct in not waiting around. Go on with your life (either with or without him in it) and find happiness for yourself, you're wasting time by trying to make him commit to something that (lets be honest) if he wanted to commit to, would have done it by now.

Don't have the sleep overs, they're just going to make things more difficult and awkward to deal with. Best of luck. :)

Most men who say they are bisexual usually end up with men. Funny that isn't it?