My best friend is off to high school, what should I do?

ok this year my best friend in the whole world went to high school and im in 7th grade. she started school the 18 and now I think im losing her I mean she wants me to do these things that will get me in trouble and when I say I cant she says these things like nobody does anything for me and you dont either but I do all kinds of things for her and she never does anything for me I think she is starting to hate me because I cant do things she can and I dont to lose my only friend the only person that dont hate me plus she is the only one I could talk to now I have nobody I cant talk to my mom cause she will get mad at me and my real dad isnt there for me. my step dad will get mad at me and I really dont have anyfriends what do I do. im lost I have nobody to talk to and nobody to have fun with what do I do and please help fast cause this year at school its horrible I suck at math and im not doin good in school please please please help me I feel like I want to cry and cry and cry please