You should realize that every 15 year-old experiences plenty of confusion and self-doubt about their life. Clearly, you are depressed, but many of the problems that you are facing are shared by every other kid that you see walking down the halls of your school.

So don't think of yourself as being more alone and isolated than you really are. In many ways, you are just one of the crowd. I'm sure you can find some other kids to talk to about these things if you open up a little. Don't shield yourself from others quite so much. Let a little sunshine in.