To differentiate both in few words we can say that BPD is a lot of problems in a single personality but DID are separated problems in two or more personalities. People with DID house personalities as if they were different people, with different names, ages, and astonishingly different genders and sexual preferences. They generally influence each other as they are connected. Yet, sometimes they are not even aware of each other.
Due to the events that follow in the novel, especially considering that Grace Marks is pardoned, the reader can infer that the idea that she is faking is discarded and with it the idea of double consciousness which will leave an open door to the theory of dédoublement. Does this position suit for Grace’s case? In order to determine if Grace can be considered as to have this diagnosis it is essential to establish the causes. It is believed that the main reason for different personalities to appear is cases of abuse and violence during childhood from what the individual or the “host” cannot defend himself. As a result, one or more “protectors” appear to help