headmates aren't just voices and I don't see why anyone should be expected to explain them as such

For me I say "voices" "head mates" and "alters". We feel comfortable calling others voices or as a it. Because that's what we thought we were. I didn't know what was going on and just kept everything in. Having to figure things out separately and learning to communicate on our own let us feel comfortable with each other as a team. And having to work together to mask in public bonds us. It's just whatever the person as a whole "host" feels comfortable with.

I always said “I don’t hear voices. I think voices. Like as if someone else is thinking in my head. I’m not hearing them like someone’s talking to me but as a thought that I didn’t have.”

Same although shouting a thought becomes clear. Like if my partner ask what we want and I hear 3 different things being yelled at once it's blissful 😒. But sometimes it's the tiny thoughts that feels off.

I have multiple personalities "voices" as many like to say. It's just something I picked up as a kid to cope with the pain. I know when I have a shift in my personality and I try to avoid people when the bad ones are present. Very hard to do.