How do I deal with my best friends ignoring me?

So it is summer and i just graduated from 8th grade and no one in my class is going to the same high school. Now it is summer i feel like my friends don't want to hang out with me anymore but i have really no other friends outside of school. My 3 best friends are always hanging out together without me and some times one of my best friends boy friend tags along too and i know that because they post it on facebook as their status. I already had a miner problem in the beginning of the year with it but now it is a real problem. Since school ended they did this to me 3 times (is what i know). I don't know if they are sick of me or are they forgetting me. Plus they won't respond to texts or facebook messages and i never see them in public. Please help me! I don't know what to do!