dear (((ladymacabethadmunsen))),
i don't know if this will help, but "many bugs are edible. however, bugs are not normally viewed as food in western culture. yet, non-western and indigenous societies have always eaten bugs. military survival manuals indicate that insects are an ideal food alternative."
(copied from the internet, i won't name the site)
so, having said that, i wonder if your alter(s) who are doing this have latched on to this fact and are resorting to some sort of strange primal behavior for the sake of survival.
i really like wanttoheal's idea of spacing out your meals more frequently so you will stay full, and keeping snacks on-hand to prevent the nocturnal wanderings.
life is strange isn't it? i'm so sorry you have to experience this type of behavior from those within. but maybe a "meeting" is in order to assure those within that they won't go hungry. please take care. i wish you well.

