Yes! That’s basically exactly what I was trying to say.
Campbell argued that dream and myth flow from the same subconscious source — that’s the secondary thesis of the book, aside from the explicit one of laying out the structure of the monomyth: “Myth is public dream; dream is private myth.”
In dream, everything and everyone is an aspect of the dreamer. In myth, then, everything and everyone is an aspect of the hero, who serves as the target onto which we, the audience, project our own self. And there are many different paths to the integration of the hero-Self with rest of the characters, creatures, settings, and objects that represent the remainder of the hero’s unintegrated whole. The hero can marry the other, defeat the other, submit to the other, become literally one with the other — those are the tests of the road of trials. But in each case, the story is one of the hero’s integration with the denied aspects of the hero’s self — or of the hero’s failure and defeat.