They don't feel like their own, sentient people

I don't know if I have some misconception about plurality or something but... It feels like they aren't able to act completely on their own. I feel like they can't take me off guard, or how to tell if I'm talking to them or I'm just imagining that I'm talking to them. Or how to tell if a thought stream in my head is a new alter communicating or just, well, a random thought train that's gonna disappear again. If I get them to say something I wouldn't expect or they do something they want to, it feels like they need some subconscious push from me to get an idea, or I have this..tiny tiny "flash of thought" before they're able to do anything.

Me: "Who am I talking to?"
: "- - -"
My head: (gr..y?)
: "Gray!"

I wonder if they are merely non-sentient "modes" I can swap into... But then, would it possible to befriend something like that?
Did I grow bonded to "people" that don't actually exist the way I thought they do...?
I don't want to lose them...

I'm so fcking confused...