In Plain Sight - Season 4 Episode 6 -

After a young Amish woman witnesses another member of her community gunned down by members of a biker gang, she and her husband reluctantly enter WITSEC under Mary's and Marshall's supervision. Soon, however, it begins to appear that her husband likes leaving the restrictions of Amish life behind much better than his wife, making it difficult for her to adjust to the ways of "the English." In the meantime, Mary becomes increasingly puzzled by her sudden weight gain, craving for sweets, and revulsion at the taste of coffee.