Review says “Mrs. March” has “fractured identity” and “imaginary friend,” but fails to consider multiple personality, probably because the novel does not label it 

https://www.nytimes.com/2021/08/10/books/review/mrs-march-virginia-feito.html

I haven’t read this novel and I don’t know what surprises or twists it may have at its conclusion. If the novel’s conclusion does acknowledge multiple personality, the reviewer would not have wanted to reveal it.

But if the novel did acknowledge it, then the reviewer’s talk of “fractured identity” and “imaginary friend” would have been spoilers, so I’m guessing that the novel does not acknowledge multiple personality.

Most novels don’t acknowledge it, because most authors don’t intend their character’s symptoms of multiple personality to indicate multiple personality, per se. They usually think of such symptoms as either ordinary psychology or nonspecific madness.