I sooo get the brush it under the carpet routine. There's so much lit out there, saying, if your child is self harming, get it attended to, listen, support, etc. (a mind blowing read, for someone who had her own stuff dismissed as a teen)
You sound like there's much more going on, than just sh. I clicked the link to your first post.
Are you serious about seeking out help?
If you are, there's forums here, to start self help, and maybe, there's ways around, but not sure, since you are a minor, getting some therapy? Have you checked out, the Addictions Forum, SI forum, and perhaps check out bi-polar and personality place, to perhaps find your way back, to being a shining role model, for your little sister?

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