kadssdak wrote:the one of us it is about isn’t being believed
I am not sure I understand properly so I will give a few answers and you pick the one most fitting.
The alter is not believed by the doctors: the doctors lack information about DID or misunderstand what the alter says. Some doctors might think it's not possible for non-human identities to happen. Some doctors might think the alter is litteraly saying "this is not a human body" so they answer "not possible" since the body is obviously human. But the alter's identity is not human.
The alter is not believed by the friends: some people are intimately convinced it is impossible to have a non-human identity despite peer-reviewed proof that some people do have a non-human identity. If science cannot convince them, nothing will, I'm afraid.
The alter is not believed / listened to by the rest of the system: this might be the reason why the alter developped a non-human identity. If the alter contains memories, emotions, thoughts... that the rest of the system is uncomfortable with, the system might push the alter away so the alter feels "not human" because they are not accepted by the system.
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There are many case reports of DID people with non-human alters. And many case reports of people with less dissociation than DID and at least one non-human facet to their identity (otherkin, therian, fictionkin, tulpamancy, daemonism...)
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If it helps you that I list my personal Pokédex of identities, I have (still active or who became inactive): fictive characters (Sherlock Holmes, Watson, Aragorn, characters from mangas...) - a Pokémon - an angel - a faun-dryad - a faun-stayr - some sort of incubus vampire demon - a qilin (chinese dragon-unicorn) - a couple homunculi (artificial humans made with alchemy) - an elf - ghosts
So, it makes me a bit confused when I hear people say that it's not possible to develop a non-human or a fictive identity. Coz I'm packed full of them and I'm pretty sure I'm (beaver-made

) dam real! (and full of dad jokes too)