She Used to Be Mine

Bareilles wrote the music and lyrics and produced with Neal Avron at Electric Lady Studios. After a lunch in 2012, a song arrived in the director Diane Paulus's inbox, and Paulus was so unbelievably moved; Bareilles called it the inroad into finding her voice on behalf of the characters. In the show it is Jenna's reflection on who she was. Per Wikipedia, Bareilles said in a Reddit AMA that she wrote it for the film scene where Jenna loses hope of rescuing herself. It is in F major with a vocal range from F3 to D5, for piano with guitar and drums.

The single was released digitally on September 25, 2015 and went to hot adult contemporary radio on September 28. It reached 26 on the adult pop airplay chart, 49 on digital song sales, and later 72 on the UK downloads chart (2019) and 24 on Scottish sales (2020); the BPI certified it silver in the UK. Entertainment Weekly's Madison Vain called it delicate, nostalgic, and wonderfully theatrical, and the New York Times' Charles Isherwood called it the high point of the show. Jessie Mueller recorded it for the 2016 Broadway cast recording and Jennifer Nettles included it as a bonus track on Always Like New. Bareilles and Mueller performed it at the 70th Tony Awards in 2016.