The singer, who just turned 34, released the emotional music video for the song on Thursday. The clip shows Lavigne like never before: vulnerable, yet indestructible, visualizing her fight against Lyme disease, the “hardest battle I’ve ever fought.”
“It makes my heart so unbelievably full to premiere the #HeadAboveWater music video for you all today, on my birthday,” she wrote on Twitter. “From the very first day I started writing this song, I have been inspired and gathering visuals and imagining what the music video could look like.”
Following the song’s release, the “Complicated” singer told PEOPLE that while she was sick, “I felt like I was drowning.”
“One night, I thought I was dying, and I had accepted that I was going to die,” Lavigne said in a statement shared with PEOPLE earlier this month. “My mom laid with me in bed and held me.”
The pop ballad’s video shows Lavigne in a white dress near a gloomy ocean view, as she sings lyrics including: “Don’t let me drown, it’s getting harder / I’ll meet you there at the altar / As I fall down to my knees / Don’t let me drown.”
Lavigne performed an emotional rendition of the song Wednesday night on Jimmy Kimmel Live! wearing a white dress similar to the one she wore in the music video. This was the first time she performed the single live.
In a letter to fans earlier this month, Lavigne detailed the pain she endured while fighting Lyme disease.
“[‘Head Above Water’] is the first song I wrote from my bed during one of the scariest moments of my life. I had accepted death and could feel my body shutting down,” the “My Happy Ending” songstress wrote in the letter. “I felt like I was drowning. Like I was going under water and I just needed to come up for air. Like I was in a river being pulled in a current. Unable to breathe.”
After the release of “Head Above Water,” which hit No. 1 on iTunes, Lavigne opened up to her fans on Instagram, saying that “writing the music that I shared with you today helped me heal.”
Earlier this year, a source close to Lavigne told PEOPLE that she “purposefully lived a quiet life” while recovering from the disease, which she was diagnosed with in 2014.
“I could barely eat, and when we went to the pool, I had to leave and go lie in bed,” she told PEOPLE about her disease for a cover story in 2015. “My friends asked, ‘What’s wrong?’ I didn’t know.”
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Now, the “Girlfriend” singer is empowering those with the same illness and inviting her fans to stay educated about the disease that changed her life. Lavigne started a foundation to fight Lyme, which she is now promoting with the new single. At the end of the music video, she invites fans to visit the Avril Lavigne Foundation website to learn more.
“Under my breath, I prayed ‘God, please help to keep my head above the water.’ In that moment, the song writing of this album began,” Lavigne said in a statement to PEOPLE earlier this month. “It was like I tapped into something. It was a very spiritual experience. Lyrics flooded through me from that point on.”