Photo: The CW

Crazy Ex-Girlfriend is closing out its third season with some very muddled introspection. “There was a lot of debate and discussion over that last song among us,” Rachel Bloom says about “Nothing Is Ever Anyone’s Fault,” the final song of the season. Co-creator Aline Brosh McKenna adds, “It was such an important song and we really hoped it would work. At the very beginning of the day when we were about to shoot it, the AD [assistant director] turned to me and said, ‘I just have to tell you, I love this song so much and it’s one of my favorites of the season.’ I could feel that. The crew really dug the song and got it.”

Bloom and McKenna alternately call the number their Love Story or Parade song: It’s a big, sweeping romantic duet between Rebecca (Bloom) and Nathaniel (Scott Michael Foster) where he tells her that they can’t be held responsible for their actions because of the psychological damage wrought by their parents. “He’s trying to justify his love for her. He’s trying to save her,” said McKenna. “She’s desperate to excuse her behavior. He’s learned the wrong lesson from being in love with her. He gives her a life preserver that is a very bespoke one, and she grabs at it.”

“Nothing Is Ever Anyone’s Fault” is the number that closes out the finale (following the other song from the episode “Miracle of Birth”). We’ll have a deep dive on the episode after it airs tonight at 8 p.m. ET on the CW.