Oh of course she's going to breakdown, who wouldn't? If she wanted her haircut, then cut here darn hair.
Brittney Spears threw a fit when the hairstylist wouldn't shave her head. Hey, as must as I don't like Brittney Spears, I still say since she's the customer and she's paying you to cut her hair then just do it. Let Brittney pay for it when she's sober (that is, if she was drunk at the time.)