Speaking with The Today Show Thursday, Parker discussed the positive message behind the book and why she chose to write it.
"I really wanted to write something most of all that was positive," Parker told Today host Savannah Guthrie. "To me, it's a bunch of thank-you notes. And it's really my rumination on the gender itself and my love of things male and men in general."
While Crudup, who left Parker 12 years ago for actress Claire Danes isn't addressed by name, her emotional state after the split is detailed in a letter entitled "Dear Mr. Cabdriver" where she details being single, pregnant and en route to a doctor's appointment when an NYC cabbie got lost.
"[Expletive], [expletive]. I mean, why, I mean why the hell-NO! Where are you going now?" Parker writes in Dear Mr. You. The situation got out of hand with the cab driver asking the actress to leave. "I don't want you anymore," he said to her. She replied: "No one does . . . Look at me . . . My life is worse than yours in this moment . . . I am alone. Look, see? I am pregnant and alone. It hurts to even breathe."
The 51-year-old discussed the passage with Guthrie while never mentioning Crudup by name. "I think it's less about whatever was going on in my life, which is private to me and will always remain so, but this was a complete stranger who met me at a very low moment. Had I been in touch with a higher self or something and been forgiving, it would have been heroic. But I was so attached to my own unhappiness that I was unable to rise above feeling persecuted."
Back in October, Danes discussed her time with Crudup mentioning on The Howard Stern Show that their controversial relationship was "really hard." "I was just in love with him and needed to explore that and was 24," she said. "Didn't quite know what those consequences might be. It's okay I went through it."