How about this? "Don't do that again."
But seriously Jababa, I'm making it a point of replying to your question because it's something I'm going through right now with my girlfriend...well,
soon-to-be ex-girlfriend!
There are two categories that unacceptable behavior from your girlfriend can fall into:
1. Isolated stupid behavior. This might include something like saying something overly harsh during a fight, or throwing her weight around, or just acting like a typical feminine b1tch from time-to-time. This stuff comes with the territory. after all...she's a woman and, by design, totally insane. The way you react to this is just to put her in her place. Tell her to keep her mouth shut instead of flapping it and losing control of herself. this stuff is the easy stuff...
2. Patterns of behavior. These are major character flaws -- including, say: weakness, instability, personality disorders, ignorance, racism, and, yes, drug addiction/alcoholism. I personally see any indicator of these patterns of behavior as a major red flag and IMMEDIATELY break up with the girl. Sure you might be wrong 1% of the time, but the other 99 cases are truly MISERABLE and will MESS UP YOUR LIFE. take it from someone who has seen it too many times. YOU CANNOT CURE HER. never wait around for a woman to correct a flaw in her character. it's basically never worth it.