Your GM in my opinion should write her up for every infarction of this magnitude, until the employee either "gets it" and behaves or is fired. Sometimes employers have to "reach" someone with the unpleasantness of consequences. A series of write ups with unpaid days off just might do the trick, however that is up to the GM to do, but you could always suggest it also. I hate when there is friction at work, sorry you're going through this.