What to do when you feel alone at school?

Basically, at school I've just been ignored by my whole friendship group and every conversation i have with anyone is just awkward now. I have no clue why they did this but it got to a point where i ate lunch by myself. At first I though it was my anxiety messing with me but i realised i don't have anyone to turn to anymore. I mean, i have a couple of friends and classmates that i talk to but we have different lessons so we don't always see each other.

It got to a point where i had to see my boyfriend from another school and eat with him when we were both free. I found that in 6 form people really start to show their true colours and friendships come and go. I literally haven't seen or spoken to anyone from school this summer. Just my boyfriend who doesn't even go to my school.

I'm known to be quite sociable yet quiet. Once you get to know me i'm really funny and bubbly. Where did i go wrong?