Depersonalization isn't so clearly defined. What you've said is hyperbolic much like what Freud wrote on the matter. Many people with depersonalization do describe such a loss of autonomy, but there is another phenomena all together regarding one watching them self from the outside typically referred to as an out-of-body experience. Viewing ones self out-of-body is distinct from the feeling that thoughts are not originating from a self.

Depersonalization could be well argued to be a type of dissociation and another type per se is typically termed dissociative amnesia implying loss of memory/function. Dissociation/depersonalization/etc.., is a normal state of mind within boundaries just like the state of anxiety.

Michah has given much more thought to such a question of existence as evident by the acceptance of the unknown, which is reflective of reality. The vast majority of people dupe themselves into believing in fabricated answers because uncertainty is discomforting. It is worth noting that identity disturbances/differences have been noticed in populations of individuals with Asperger's syndrome. Perhaps the root issue here is Michah has false expectations as to what an 'identity' or lack there of is to other people of whom she is comparing her own sense of identity to. Given the depth of thought she has demonstrated on the subject, the false expectations could be from other individuals poorly interpreting and describing their own realities.