I am not my characters. Even the ones that contain large pieces of me, even the ones where I write as "I" rather than from some degree of literary distance. We are different, they and I. I have not lived their lives, and in most cases, I would not want to.
In some cases, I do not like my characters. I understand them, I know what they want, how to write them, but I would not, if given the option, bring them to life and have them over for dinner. With some of my characters, there is a very real chance I would not survive that experience. Some of them say things I do not believe, or behave in ways I find morally abhorrent.
Except. Like Prospero, these things of darkness, I acknowledge mine. I wrote them. They live because of me. And I write what I do because I want it to have an effect on readers. They will think certain things about me because of what I write.
Still, it's a tricksy thing, to try to divine an author from her writings. Maybe what you think you know about a writer is wrong. It is, for example, possible for a writer who is not a serial killer - and has no desire to be one - to write a compelling and terrifying murderer, or for an asexual person to write a truly hot sex scene. We are, after all, writing fiction, and if we cannot imagine people outside of ourselves and the worlds they contain, well, we are in the wrong job. The text is the key to understanding the text, but it is not the hidden cypher needed to unencrypt the author's psyche.
But on occasion, a piece of an author's life will show up, and it will alter the way we see the author's work. Reading "The Wife of Bath's Tale," with the reformed rapist knight as hero, is a different experience when Cecily Champaign's deed of release, releasing Chaucer from "all manner of actions such as they relate to my rape or any other thing or cause" (omnimodas acciones tam de raptu meo tam de aliqua alia tam de causa), is taken into consideration. This document changes my relationship to Chaucer, much as my certainty that Spenser would have hated Irish, Catholic, female me, changes my ability to come to The Faerie Queene with open heart.
What we know about artists changes our relationship to their art. The degree to how it does, and in what way it effects us will vary, from person to person, and from one piece of art to the next. We are not our creations, but they are very much ours.