This sounds stupid but i'm worried about my friend?

My friend is 15, she's had sex with 3 different people, she smokes weed everyday, at weekends she sniffs ketamine, takes ecstasy and drinks at least a bottle of wine to herself. Shes been sniffing ketamine since she was 14 and she lost her virginity at 13 (she has been raped as well) shes had a hard life to be fair and her mother died 2 months ago from cancer. She also smokes heavily. I don't know if i'm overreacting or if i should do something to help her? Shes a good person but i'm scared for her and her health.