I Want To Help My Friend, Im Scared For Her

hello, my friend who has been like a sister all my life has admitted to me today that she has used heroin a few times recently and she trying to say she not addicted which i know she is, she's in denial big style, im sooo worried about her coz she ended up in hospital today with havin a small stroke so the hospital says but she never told them she is on heroin, after being in hospital 3hours she discharged herself, she has mental health issues and smokes weed and has been taking anfetamines and m-kat which she admits to, i really want to help her but coz i know about it she is starting to lie to me now, i really want to help her, ive tried sectioning her and i cant, ive asked her to go rehab but she saying she not addicted, help me please im at my witts end and she is going to end up killing herself, what can i do? help me to help her please xx
how old is your friend?