Jennifer Lopez has quietly been recording new music — but sources say one unreleased ballad stands out as the rawest thing she has ever written.

The track, reportedly titled “The Last Door Closed,” was recorded during a late-night session in early October, with only three people in the studio.

“She cried while recording it,” an insider from the session said. “Nobody had ever seen her that vulnerable. The lyrics are brutal, but beautiful.”

While Lopez has always been open about love, insiders describe this song as “the first time she truly wrote from the wound, not the scar.”

The ballad supposedly includes lines referencing coming home to “lights that stayed on but love that didn’t,” and “the echo of the promises we never kept.”

Producers say Lopez debated whether to include it on any official project because it reveals more about her breakup with Affleck than she has ever publicly admitted.

“She’s terrified and proud at the same time,” the source added. “It’s the closest we’ve gotten to the real Jennifer in years.”

Fans are now speculating that the song may appear in her upcoming musical project — but nothing has been confirmed.