School is definitely hard, I had a hard time coping too when my friends weren't around. I would even pretend to be sick and try to stay home if I knew they wouldn't be in. I just did my best to try and make a few more friends. If you help someone in class with their work they (or you) will probably feel comfortable enough for a simple "hi" in public, and you'll build on that.
I used this when I started college, it helped me make some friends so I wasn't alone. Being alone in school isn't nice and I hope you can make a few more friends.