What to do the rest of highschool?

I'm in highschool and one of my best freinds dropped out, my other best freind is now going to military school and my other really close freind made a new freind and is hangingout with him all the time. It seems like all my real homies from middle school are disappearing . plus I'm going to be a junior next year and I'm not sure what to do:/ any advice?