As you probably know, Carl Jung was one of the fathers of psychology, but his work didn't quite survived to these days as a whole. Psicanalysis has only some influences from his work, but his main ideias were discarded to parapsychology.

One of his theories was the Colective Subconscious and the archetypes. The New Age'rs of today do really like the colective subconscious ideia to express the holistic notion that we all are One.
Jung wrote that deep within our race lies archetypal structures of behaviour that are predetermined and most of these behaviours are projected to mythology and works of fiction. That's why many complexes in psychology were named after greek mythology (ex.: Edipus complex, Zeus complex,...)

There are three of these archetypes that I find most interesting: the Anima, the Animus and the Syzygy (spelled "ssízíguí" in portuguese).
The Anima is the feminine spirit in a man and the Animus is the masculine spirit in a woman. Together, they form the Syzygy. There are countless places in fiction and mythology where you can find these archetypes.

I think this sheds a light over my own head. I have a Anima with a very strong presence, almost magical in nature. I still wonder what she is and what is her function in my psyche. I believe my Anima is some trick used to prevent me from going mad, or she is a projection of my desires.

Whatever she is, whatever she seeks, I want to give in and let go myself, there is no sanity left to save.