Out of boredom, I decided to make an account to share what I think on the situation with Ginger and Licorice.
Lico never had a physical body outside of Ginger's, even in the nightmare realm.
Notice that the only one that ever paid attention to them both is Mindsnare(which could be due to his connection with minds, or something) and Bleedheart(another supernatural being, could possibly notice a personality shift due to being able to read minds with like Brave), and they never both 'psychically' interacted with something at the same time.
Try to imagine, when they're both talking, that one voice(and body) is only in her mind, and the other one is what she's saying in reality, switching from time to time. Along with their interactions with each other only being in their mind while the body is doing something different.
Like in the encounter with Bleedheart, imagine the only voice people are hearing is Licorice's(along with the only one they see) and that Lico actually looks just like Ginger until shortly after Bleedheart throws her then the real Ginger starts talking, at which point the attention shifts to her.
Notice how when Bleedheart grabbed Lico, the shark and the plantgirl only paid attention to Lico, like she was the princess and Ginger wasn't even there at all?(along with them both saying the same thing at once) Heck, they never even thought about why there was two Gingers(there wasn't).
Then after that scene, Lico disappeared from anyone else's view until this scene, when Ginger is thinking to herself.
Both Bo and Hansel never seemed to notice any kind of wardrobe shift(from pink to black clothes) ether, suggesting she wasn't wearing them in reality.
I say it's a very clear split personality disorder except nether goes fully dormant, it's just which side is dominant at the time is the one really speaking, and they see the other(Schizophrenia); but their dialogue and interaction with each other is really just in Ginger's mind(though Mindsnare could see their "catfight" which was probably just a small fight for control), so when talking to each other, to everyone else(except Mindsnare, maybe Bleedheart) she looks like she's talking to herself.
Heck, the Ginger we saw in the beginning might have been Licorice talking most of the time.
But that's just how I see it.