BIPOLAR AND THE VANISHING TWIN.
Have you ever heard of the Vanishing Twin? When a woman is carrying twins, sometimes one body dies and the souls merge. It is not two souls in one body. Half of each soul becomes a united single soul. I actually know someone who said this was her story.
This is how some people have dual personalities. Each soul has a personality. Sometimes soul A is in control of the mind and sometimes soul B is in control of the mind. What is needed is to have the mind become of one mind so to speak. This can be done through spiritual healing. Hypnosis and meditation can help.