I haven't read your story or been in your shoes, but I can empathize. Have you tried speaking to your parents about how you feel? Or a teacher, or a guidance counselor? I'd say a friend, but honestly at that age, they probably aren't emotionally mature enough to address such a serious situation.

Sometimes families don't realize just how much a child internalizes until it's too late. So its a great thing that you recognize your stressors, your coping mechanisms, and that they are maladaptive.

For trying to stop, I know a lot of people suggest the rubberband method (wearing a rubber band on your wrist and snapping it when you feel the need to self harm). In a way its still self harming, but its a great way to have less permanent effects. You could also draw, paint (even if you're not good at these things), listen to music, take a walk, scream into a pillow, bake cupcakes, build a card house, or really do anything that can divert your attention and those negative thoughts.

I would also suggest maybe joining an activity at school, or an after school program. Not only would these things distract you, but they would take you away, even if temporarily, from the source of your stress.

Good job on being clean for two months!! Thats a very big deal! You obviously have great determination, so good for you =] I hope you feel better!