Then something unexpected happened. When I realized I was done writing the series, I began to miss the characters I had created. It was the same feeling I had when I retired from teaching and began to miss the kids and classroom, or my colleagues. These were, at least in my mind, were real individuals. I had spent over three years developing them, and learning about them, and came to care about them. I felt sadness when I had to have some of them die to advance the plot, but now I was never going to see any of them again.
I guess this is why many authors, at least many of the ones I know, are mostly loners. Our characters fill our heads and don't leave much room for a lot of other people. Or is that just me? Authors frequently say the characters of their books tell them what to write, so I suspect it's not just me at all. These folks are apparently real as far as my emotional state is concerned, and I will miss them.
I hope I can develop a similar relationship with the characters of my future books.