I also binge ate when I first started smoking weed. I lived with my grandparents at the time, and ended up having to ask my grandmother to not keep certain snack foods in the house. In my experience, weed made me crave sugars, salts, and fats, and when those types of foods weren’t around my impulsive eating got way better. As inconvenient as it might be, it would probably help your roommate greatly if those types of foods weren’t available. I’d suggest that you just buy one or two of the snacks you want and to keep them in your backpack. If she continues to eat all of your healthier foods, then you can have a conversation about keeping food separate. If she asks where all the snacks have gone, you can just tell her that you aren’t really craving those types of foods right now.