In Rebecca, the heroine is the narrator, but she is also nameless. We know her only as Mrs. DeWinter after she marries Maxim DeWinter, although Rebecca was the prior Mrs. Dewinter. By not giving the narrator and heroine a name, the author symbolically illustrates that the heroine is living under the shadow of the prior Mrs. DeWinter and until she can be rid of Rebecca’s ghost, both literally and figuratively, she will not be able to thrive and her marriage will be doomed. Also, the narrator was an ill-treated orphan, and until she marries and takes on the name of her husband, she is a non-entity (a Victorian thing). The lack of a name also illustrates the insecurity of the narrator in the beginning of the novel, trying to live up to Rebecca's memory but not really understanding until the end that this is not a good thing.
As the novel progresses, the reader slowly learns that while it appears that Maxim loved Rebecca passionately and his new wife can never replace her, this is very far from the truth. Mrs. Danvers, the evil servant who was and still is psychotically devoted to her dead former mistress, has hidden the fact that Rebecca was a purely evil woman that Maxim did not love. Mrs. Danvers hides Rebecca’s true evil with her own evil.