Private
That's better than random voices hon, trust me. Cherish that one, I think is best.
When you start having conversations with yourself you learn to do them inner-monologue style. Or at least privately. I've manage to make a giant library in my head, stuffing most of the older, quieter voices in their own little sections. Pulling them out when I need them. It's not perfect, I'm still not there with the last big batch. You can figure out how to store the imprint so it won't interfere with day to day, then pull it out when you want comfort.