I've improved my thinking speed, and sometimes I feel like I'm talking to myself as two separate individuals, and I think it could be another person's soul that I may have attached to myself and I can't literally talk to her for more than a few minutes, she says she's tired, but at the same time she cheers me up and gives me arguments or scientific data.
Discussion
Active TranslatorIf you both hear and talk to a voice or perception, medically you could investigate better.
Spiritually, do Void Meditation when you hear that voice.
Dissociative Identity Disorder is "real" in the sense that it is a real mental illness, where the person can genuinely feel as if there are two or more wills and minds controlling the body.
In your case, people can naturally have dissociative-like behavior, maladaptive daydreaming, derealization or depersonalization, etc., especially if they are young (not enough time to form a more solid sense of identity) or had a traumatic childhood.
For a 6 year old, having a voice in your head that you vividly visualize to appear real is a fine way of thinking and exploring life.
For an adult, this is a sign something is wrong mentally, as one's sense of identity is very important to lead a healthy life.
Seek help.