I can relate to what you are going through. I had tried to talk to my guidance counselor and she didn't take me seriously. I would consider trying to find someone to talk to. I discovered that a neighbor down the street was a social worker and ended up venting to her some. You might could find a teacher whom you could atleast get some of your feelings out to. As for treatment for depression (if you end up having it), a person your age is allowed to seek treatment without parental consent--I think. So, if you need it, you might try talking to some one at your school and see what the confidentiality policy is. This policy gets complex when it comes to a minor. I had to wait until college before getting treated for slight, long-term depression.
I hope you find someone who is take you seriously and help you. It is very hard to live with what you are going through. Feel free to post here any time you like.