Let me get this straight. You wrote a story about a writer, who writes about a fictional dream girl that magically comes to life. You were then cast as said girl (Ruby Sparks) and brought her to life on screen, yourself. There's two ways to look at this. One, you just cleverly wrote a dream part for yourself to play, and then did. Or two, this film is not just thematically, but literally, the manifestation of a meta-physical crisis whereby your unrealistic, self-absorbed standards of perfection have come to life in order to teach you a lesson.
To be honest, both possibilities only deepen my affection for this perfectly charming indie film. But after seeing your name all over the closing credits, I can't help but add my own narrative.
So you, Zoe the writer (and granddaughter of legendary director Elia Kazan), write a screenplay called Ruby Sparks that centers around a young prodigal male authour named Calvin Weird-Fields, played by your real-life boyfriend Paul Dano. Calvin is a loner who dreams of meeting a girl that fills all his fantasies of what a girl should be - cute, quirky, completely affectionate and unwaveringly loyal. But since you are the original author, these are either your own self-projections, your own desires, or just your interpretation of the male fantasy. Either way, you suddenly appear as Ruby Sparks, and embody them all. Which, at least initially, seems to be a dream come true for everyone involved - fictional and real.
Especially Calvin, who has absolute power over Ruby. She immediately becomes exactly what he writes, even though he initially vows to never tinker with his original design. But who can resist, right? This probably parallels your own power as the film's screenwriter on set (and executive producer), able to tweak dialogue to suit the given mood. That seems to serve you well, as the character exchanges feel authentic and unhampered by heavy exposition. But like Calvin, you were probably kept in-check by forces around you, such as real-life couple Valerie Fairs and Jonathan Dayton, directing their follow-up feature to Little Miss Sunshine. Their ability to delicately balance the comedy and drama shines through, helping the film avoid the hammy territory of The Odd Life of Timothy Green, while keeping your story more accessible than it's obvious inspiration, Adaptation.
The film is actually at its best when it starts deviating from expectations. Going to some dark places helps the story avoid the potential pitfall of being just a romantic comedy with a twist, and elevates the whole experience to the rather profound. But that's just for the audience.
For you, it was actually life changing.