Is my best friends life on danger?

Hello, I am very worried about my friend. I think she is very sick but won't tell me ör anyone. It started like 5 months ago, she take pills all the time in school and if she dont take them she starts to bleed through her nose and sometimes she faint. Then last month she was at the hospital in 3 weeks and then came back to school, she said it was something wrong with her eyes but I dont believe her. She always tell me she have major depression but still dont want to tell me, then she always say that her hair fall because of the pills she take and then she always tell everyone : " Use your time with me, I may be gone/ not be here anymore". And sometimes she say " I dont think I will live any longer than 16"( she is 15) and sometimes she ask a friend of mine if cancer have any treaments. I am VERY worried and I still dont know what's going on, she keeps telling me its private on what happened to her in the hospital. She also have to go to the hospital 1/week and that they take blood and do something with her. But I dont understand whats going on with her.. Any tips?
Is my best friends life on danger?
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