Ending a friendship.. problems?

Ok, first off, no matter what you say to her, there will be drama. My advice is to calmly explain to her that you guys have grown apart. DO NOT do this via, facebook, text or email. Meet with her in private or at least call her. Remember, it's not going to be a clean break on her part. Even though you might feel bad for her, do not go back to being friends with her against your will because you will regret it in the end. I have went through something similar and I attend a school that has 30 kids in my grade, so I know what it's like to feel like you can't escape her. I wish you the best.