a major dilema

hey...
heres a problem that a friend of mine has...
if you have any input, leave a comment, email me, or talk to me at skool... watever,
just major advice needed.

a friend of mine did pot a couple months ago. she told me it was only a one time thing.
then she did it a couple more times...
when i started getting worried, she started making promises.
now she's doing it again.
when i said "didnt you promise me you werent going to do pot/"
she says "i realise that i broke that prosmis to you, but to tell you the truth its not going to happen again cus i do it anymore if i want to keep playing volleyball"
i say "i dont care that you broke a promise to me, its alot more important than that"
then she asks "speaking of which what nights do you practice?"

i said "we'll talk about that later.
i'm not even sure what to tell you
i want to tell you that your being a stupid ass, but thats the wrong way to go about it.
then i could list all the reasons its bad. but you've heard all those before.
i could remind you about my friends in NY, who nearly OD last year."

then of course, she relieves all my worry (sarcasm) by saying "and its fin julie, i made the stupid mistake of doing it a cupple times. but i have now found my "anti-drug" not to sound corny or anything but i wont be doing it any more and ive also given up drinking."

o ya. theres a whole load of shit i dont need right now.

any advice would be greatly appreciated.