1. The Container Store sells lockers for the refrigerator to prevent roommates from "borrowing" your food. The Sage suggests that you invest in one. Try the internet if there is no store like this near you.
Since the parents may already be aware of this dangerous habit, someone should talk to them. She sounds unbalanced, and their intervention could save her life.
2. The Sage notes that he gave you notice that booze is more important than any of his friends. The Sage is surprised any of you kept him in your circle of friends. He obviously is not one.
3. The Sage recommends that you tell her she is acting like a stalker. If she gets upset or continues, de-Friend her and block her number. Consider changing your own number. Send her a copy of "Single White Female" as a parting gift. Consider a restraining order if she does anything threatening.
The Alternate Advisor's phrase is backwards. The correct phrasing when using "let alone" is to list the easier item first, and the harder item next. That is, she should have said, ".. it was impossible to send one text in one evening, let alone 47 texts." The Sage wonders if this Alternate Advisor actually attended journalism school or even took a writing class.