Mate, even if she lived in the next room to you, if she wanted to self-half, she'd do it. When it boils down to it, theres nothing you can really do apart from just be there for her.
Instead of trying to get her to just stop self-harming, try and find something she can do to releave stress, sports and martial arts work very well for this, yoga, there are all sorts of things she can do.
She's only human and we all need some release of stress/anger or it becomes too much. Im the perfect example of someone who never releases stress, i keep it all bottled up and to myself, and dont, would never self harm. screws with your head after a while
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