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I'll get right to it.
My best friend has been my best friend for six years.
We've always been so freaking close close enough to be mistaken for siblings.
He's like that crazy friend who understands all my crazy.
So we've started the first year of 6th form (I think that's like 11th Grade to any Americans out there) and it started great, we had two free lessons together which we used to study together, went into town for lunch together, stuff like that.
He has the same lessons with these five people.
three of which I know well, the other two are acquaintances.
But now he's spending every second of the day with them, they all have so much in common besides being in the same classes.
At first it was okay, the more the merrier, more stuff to talk about and all that jazz, but then I started feeling awkward because none of them really had any interest in me or anything I said.
After a while my friend stopped spending lunch in town with me, he stopped spending the free lessons with me, I only ever get to speak to him in form time, because we have the same tutor.
Even there he speaks to somebody else (coincidentally, the guy who used to be one of my best friends, but ditched me).
We used to talk on FaceBook chat all the time until the early hours in the morning, now the chat history is full of just me saying "hello" and variations of every couple of days, so now I just glare at the little green active icon and say nothing.
I'm friends with his neighbour and she's noticed it too, and thinks it's just plain rude and keeps dropping hints that he occasionally picks up and starts talking to me a little bit.
The other day I decided to do a little test, since I am a super loud and talkative person, I decided to just sit there and say absolutely nothing to him all day and see if he noticed.
He didn't.
I think he's being rude and awful and taking me for granted, but then I feel awful and rude and selfish and self centered for thinking that.
I'm bad at making friends, especially close friends, I used to have three really close friends but now I just have the one, and I feel like I burden him with my clinginess and constant need for conversation or anything to prove he still gives a s**t about my existence.
So I'm feeling terribly lonely, and my entire social life has been a cycle of the exact same thing over and over again so I have little desire to go out and make more friends because I'm afraid it'll just happen all over again.
I hear people b***h about people from their respective friend circles and it horrifies me and I feel the need to remind them how lucky they are.
I feel like I'm just that friend nobody likes, that I'm a boring, repetitive and unlikable person, and it's killing me.
Any advice? Anyone who had the same problems once upon a time and wouldn't mind sharing?

I know how you feel, I had a really good friend for years, we did everything together. She was friends with everyone, but it never bothered me too much when she was with other people because she can be around anyone she wants.
But one day, during a choir lesson, she sat next to one of her other close friends. I didn't mind, until we left the lesson and she gave me an evil glare and linked arms with the other girl beginning to laugh about something.
I wanted to believe that I was crazy, but I still couldn't shake the feeling that she really had started to hate me.
I brought it up to her one day, telling her that I felt like she didn't want to be around me anymore. She told me that she would never stop wanting to be around me.
End of the school year, she never signed my yearbook like she normally would. I texted her later, asking if she was okay and she told me she wanted nothing to do with me.
I was really devastated, going everywhere for advice, the internet, other friends and family.
The best advice I was given was to try asking her what happened. If you've known your friend for 6 years, he should be able to understand how you feel. Don't let it scare you. Sometimes expressing your feelings can help the best.