Friend troubles..please help?

Okay, so a few months ago my bestFriend moved away. And I've become alot more dperessed than I was, and like they say ' you don't know what you have until it's gone'. Well everyday i'll post on her wall or send her a message on facebook hoping she's okay, and that i miss her and love her. We have been bestfriends for years. And been through everything together. But my other mate is apprently in love with her because they're both bisexual. My friend only reveleaved she was on the night she was leaving though when we all had a massive sleepover. but on that night she didnt know and niether did all of us know she was gonna go the next day. Until on the sunday of that weekend I got a phone call saying she was on the train. Anyway my bestfriend is seeing my other friend, and my other friend is abit of a control freak and always gets what she wants. And does whatever she wnats, and the world basically evolves round her. Anyway my friend always takes the mick out of me for everything and always calls me pathetic because i self harm and that im down. And today my best friend is coming home to see her dad and us. But we're all having a bbq tomorrow with her. But my bestfriend keeps asking her ' can we' have an hour or two hours away from everyone else' and its like my bestfriend will only be there for a few hours, and if my other friend is gonna take her away for an hour its not fair becuse im her bestfriend. I know they're inlove but its i'm her bestfriend at the end of the day and i've been there for her for years. And as soon as my friend likes her its all about her, and now she thinks she can control her and stop me from seeing her for her benefit. I just want to see my bestfriend and its causing so many arguments with the rest of my friends and im getting called jealous, but im straight. And i know that my friend will cheat on my bestfriend and then if it was the other way round she would bite my bestfriends head off for doing that. It's not fair i love my bestfriend too, and missed more than anything in the world. I pratically cry about her every week. But my friend keeps saying ' im her girlfirend you're just her mate' like im nothing to her, but i love her and i miss her so much and i feel i cant see her because im not as important.. please come up woth something i should do. But i think my friend is turing my bestfriend against me, because she keeps sending messages to my bestfriend saying that ive been saying nasty things to her. But all ive been asking is that we should stop pestering my bestfriend to come to each of our houses because we shouldnt make her feel pressurised but then my friend was like ' i do what i want, and your ruining my relarionship, what do you want me to do finish her? thats what you want' and calling me a control freak, but all i want to is see my bestfriend, but apprently im not as important. But my bestfriend is very vunerable and will agree with everything my friend says, because my friend is very intimidating and powerful. So I know whatever my friend asks my bestfriend will jump to it. I just dont know what to do, I cant do anything and im losing my bestfriend and once my friend has had eough of her everything will be ruined and i would have fell out with my bestfriend. But we once met her at shopping center and she was going on our train to get home, and i asked her at the beginning of the day ' can i sit next to you' and she said yes but then my friend asked her just before we got on the train and i said i've already asked her and then she was like ' why cant i just sit next to her, im the one in love with her and we're seeing each other' and then all my other friends were calling my jealous, and my bestfriend was stuck in an awkward position, but eneded up sitting next to her. And now when she comes down, my friend asks ' dont start crying if i take carla for some time with me' but its like shouldnt we all share her. Its just not fair, i know they're seeing each other but as soon as my other friend wants something im pushed out of the door.