I think it's because I spend days and days with my characters. I think about them almost constantly. I wonder what they're doing, how they would react in certain situations, what they would say. Bits of dialogue appear in my mind, almost like I'm hearing the characters say them. I can close my eyes and see their faces and what they're wearing.
My characters live interesting lives. They deal with murder and secrets, love lost and found, danger and thrills. It's easy to pay attention to them; compared to real life's mostly boring chores and duties, my characters are fascinating.
There are times when I've felt my characters speak to me so strongly that I've worried they might be overcoming my personality or I might be developing multiple personalities, some of whom should definitely not be allowed in the real world. But then I finish the story, and they go away, safely tucked away in a book.
Until I start writing again. And there they are, just waiting for me to give them life again. In some ways, it's a bit scary. But in other ways, it's exhilarating.
(This post is part of the 2013 Blogging From A to Z April Challenge. Learn more about the Challenge HERE.)