Relationships are hard, and I'm not only saying that girl+guy are the hard ones. Friends are especially important as your someone special. I first suggest that you clear things up with your friend, because friends are for life... even if love isn't.
I'm not saying that love isn't for life, because for some it is... others not so much. That's beside the point. Like Sayuri has said, try hanging out with her and avoid, drugs, smoking and what ever else you thought would help. Really, the people only do it to release the pain they have inside, maybe stress. But, if you don't do any of those, you can show that you don't need any pain killer to get rid of emotional pain. I suggest for now to be friends, and maybe things will work out later.
I understand completely, and don't let others judge you. You are you, and that makes you special. I understand high school relationships and I wish for you to understand that things do happen... things that aren't pleasant. If you keep your friends close though, you will always make it through it. Life is for living, so why not live it?