I can’t speak for other writers, but I suspect many of them feel this way. By the way, the whole reason for this post was in thinking about the idea transplant rejection and the film Inside Out. See, writers have little people running around inside their heads, but we call them characters. And I’ve got a whole weird cast. And they keep getting weirder.
I remember an essay I wrote for when I took Eng 101 many, many, many moons ago that asked me to identify different parts of my personality. And I did. Each one was a character. There was the chess player, the knight, the inventor, the assassin, and a slew of others (I can’t even find that essay, now). But each one encapsulated different aspects of my personality, with plenty of crossover.
Now, however, I’ve got dozens, if not hundreds, of characters swimming around in my head. And most of them are yelling that it’s their turn to drive, and that I need to get back to writing their particular stories.
So far they’re content to take turns (though some can get pretty vocal), but I know that there are unlit passages in my mind containing more characters, more locales, and they, too, will want their time.
In short, if you have a friend who is a writer, this is why they’re crazy: too many people trying to drive at once. Hey, you try sticking an afterburner on your imagination and see how you do.