"It's something in my life that's always really kind of defined me up until this point. In a strange way I feel like it won't define me anymore after I sing it on TV at the Oscars, if I can let it go maybe," Gaga said in a recent interview with The Associated Press.
Gaga, 29, was sexually assaulted when she was 19. "Til It Happens to You," written with Diane Warren and a nominee for best original song, appears in "The Hunting Ground," a documentary about sexual assault on college campuses that was directed by Kirby Dick.
The pop star said earning her first Oscar nomination for a song about a serious and heavy topic "makes it extra-special."
"They really and truly nominated the issue of sexual assault on campuses. ... People all over the world that have suffered with any kind of pain or trauma, (if) they are having trouble being brave, this song is for them," she said.
Gaga also said she's honored to be nominated with Warren, who earned her eighth Oscar nomination with "Til It Happens to You." Warren has never won the prize despite earning nominations for No. 1 hits like Aerosmith's "I Don't Want to Miss a Thing" and Celine Dion's "Because You Loved Me."
Warren said she took a risk calling Gaga and asking her to work on the song.
"She publicly talked about being sexually assaulted herself and I thought, 'You know what, I'm going to just take a chance and call her and see if she's open to this.' And you never know because someone can get pissed off or something if it's too personal, but she really responded," Warren said. "I got on a plane and we went into the studio."
Some drama clouded the good news of the nomination when songwriter Linda Perry, who has worked with Christina Aguilera, Pink and others, insinuated on Twitter that Gaga didn't write "Til It Happens to You." Best original song nominees only include songwriters, not the singers. Perry later apologized.
Warren rarely writes songs with others, but said Gaga played a large part in the song.
"She put enough of herself in this to where I felt OK about it. I felt that it was a collaboration," Perry said.
Other best original song nominees include Sam Smith's "Writing's on the Wall," The Weeknd's "Earned It," David Lang's "Simple Song #3" and "Manta Ray" by J. Ralph and Antony Hegarty. U.S. Vice President Joe Biden will introduce Gaga before she performs and he will urge Americans to speak out against sexual assault and support the administration's "It's on Us" campaign.
The Academy Awards will air live from the Dolby Theatre in Hollywood, California. The show starts at 8:30 p.m. EST (Sunday, Feb. 28) on ABC.