HI and welcome!
Well it seems she's let it take hold of her, not pupoesfully I'm sure. Thus addicts result. But I'm afraid your concern is about as far as your going to get in helping her see it's begining to be a problem. She's probably obsessed with the high, can't seem to function anymore without the buzz, and does not realize, her "self" is deteriorating away, layer by layer. Unless he has specifically asked for help your attempts to make her, help her, or force her to quit will be futile and she'll eventually resent you for it, which is "her addict self" speaking to her. Right now she's still in the "party on" phase, and she won't see or realize what you do. Eventually, she'll get to the "hopeless" stage, and hopefully, then be willing to get help. Good luck, we'll be praying for her.