When I was trying to figure out what was going on within me I was researching Native American lore, etc, and found MANY references to two-spirits, Those who share mind and body with another. This is where I believe a lot of the Therian ideology has it's base, maybe not in Native American, but in the belief that the body can be shared with another spirit.
This is how I see myself, Naake ni (Apache for Two Spirits, the title is a real thing)... I consider him "My wolf" though he is not a physical embodiment but the wolf within. When he is active I see and interpret things differently, I feel different on a deeper level, and my personality shift to a more aggressive, more dominant (IE: Alpha type) place. Even my mate (my wife) can tell when Naake ni is closer to the surface.
He 'influences' me, not so much with words, but with visual imagery and emotion/feeling, and has led me to go places and experience things that I cannot explain or would have done on my own.
I am not saying you are wrong for you, but I disagree with your hard and fast statements that tell me that what I feel is not real.