Every major character finds different interpretations, as each author, reader, etc. identified in its own way with her. But this little masterpiece is true in my opinion proverbial bull's eye of Batman's soul. Diving takes place in the dark substance that makes the Dark Knight to what he is. I never came to a meeting the description of his psyche in touch.
Past / present of Bruce Wayne / Batman condense in this presentation to what Batman's existence characterizes ... and forms a violent "... blow in the pit of my stomach ..." - constant pain.