In conjunction with the release of her memoir, Open Book, and its accompanying audio book, the 39-year-old singer also dropped six songs, her first new music in nearly a decade.
When ET recently caught up with Simpson, she opened up about how making her new music was a cathartic experience amid her struggles with alcohol.
"The music is actually everything that inspired me to get sober and write the book," she said. "Because I realized when I was going down into my studio, even though I was in the comfort of my house, I had to drink to numb the pain that I was about to experience to write."
"Songwriting takes me to an honest place, and honestly, I was in a dark place," she adds in the book. "I just didn't know it until the words came out of me."
Tune in to Tuesday's episode of Entertainment Tonight for our full interview with Simpson. Until then, keep reading for a song-by-song breakdown of her new music.
The powerful anthem is one that Simpson wrote when she hit her three-month mark of sobriety.
"[It] came out so easy, and I finally felt unblocked," she writes of the track. "I could put words to feelings again and make them mean something for other people."
Throughout the upbeat, empowering song, Simpson celebrates living her life happily after the pain of her past.
"Now I only dream in colors / When I lived in black and white / You grow up fast when you're a mother / You stand strong when you're a wife," she sings. "I made friends with the past / I'm not ashamed / Let all the tears roll down my face / Wouldn't know all this beauty without thanking my pain."
The guitar-backed, mid-tempo track features Simpson singing about making a choice to stay in a relationship. She and her husband, Eric Johnson, tied the knot in 2014 following her 2006 divorce from Nick Lachey.
"Years of giving over / Heaven knows I've paid my dues / We're not getting younger / But we've still got time to lose," she croons. "So I don't want nobody else / No I don't want nobody else."
"I could leave if I want to / These walls are made of stone / But they don't hold me," Simpson continues. " I'm not a prisoner / I'm here of my own free will."
"Party of One"
After Simpson fired her dad, Joe, as her manager in 2012, she held off on playing him any new music until October 2017. "Party of One" was the first song she played him, and it was an emotional one at that.
"[It's] about how abandoned I'd felt by him and my mother choosing the very moment I needed them most, becoming a mother, to go off and start their new lives," she writes in her memoir, referencing her dad's decision to tell her that he was divorcing her mother, Tina, while she was in the hospital pregnant. "I'd never been brave enough to tell him I was mad at him."
"I watched his face as he listened, eyes closed. I don't know what I expected from him. Anger? That he would leave? He didn't. He got up and put his arms around me until I shook with tears," she continues. "'I'm so proud of you,' he said. For the first time in my entire life, he was responding to something I created not as a manager, but as a father... He just said, 'I love you.'"
On the track, Simpson wrestles with her conflicting feelings for her dad and how they had made her question herself.
"I hate you / Lie to you / Sometimes I don't give a damn / A damn about you," she sings. "I love you / Breathe in you / I know that I will die with you / It's time that I look in the mirror / Straight in my eyes / Tell myself I'm not broken / Just 'cause I cry / It's a love song / Party of one / I'm not weak 'cause I don't want to fight."
"I am more than my body / More than my wealth / I am more than these demons / Holding me down / It's a love song / Party of one," Simpson continues. "I know it's bad for my health / I am somebody / Just stuck in this body / Finally I don't wanna leave / So hey it's nice to meet ya / Every time I see ya / You're not a stranger to me."
"Practice What You Preach"
Simpson describes this track as a "direct hit at" her father, one she wrote because "his choice to leave my mother was like a bomb going off in my life, and I still found myself clinging to whatever I could hold on to."
"He didn't mean to hurt all of us so badly, but I knew for a fact that he had realized his decision would have consequences. I know he knew that because that's what he had taught me. But I had kept that from him," she writes. "And now I needed him to hear that I was singing about him."
"... I was standing in judgment of someone who I felt had compromised his values," she continues. "As he listened, the blood drained from his face until it was ashen. What have I done? I thought. He nodded, started crying, which got me crying. 'Jess, it's beautiful,' he said."
On the emotional track, Simpson sings, "You taught me how to love somebody / Just like you / You taught me how to leave somebody / And it's hard to do / You said keep my s**t together when the world unravels / And put a brave face on in the heat of the battle / So that's what I did"
"Go and pick up your head / Even if the higher ground is the place you've forgotten," she croons later on the song. "May your actions speak louder than words / Give them hell / As hard as it hurts / 'Cause that's what I learned from you / So take it from me / Practice what you preach"
"Standing in the middle of a broken road / I've been searching for an answer," she sings. "Back in my mind I've always known / If I turn around I walk alone / If it makes me better maybe that's the road that leads me home."
"Maybe that means I'm doing nothin' / Maybe that makes me more alive / The angel on my shoulder sittin' on the devil's side," she continues.
Sweet temptation / Always turnin' me on / Sweet temptation / Throw myself at your arms."
Simpson ends the question track by crooning, "There's no amount of prayin' / There's no amount of will / There's nothin' gonna keep me / From climbing up the hill / Sweet temptation / Are you leading me home."
Featuring her good friend, Willie Nelson, Simpson writes that she wrote the track alongside "producer John Shanks after pouring my heart out to him about what my friendship with Willie has meant to me."
One line in the song, "I chewed out the moonlight / Lasso all the stars," came when she was putting her 7-year-old daughter, Maxwell, to bed.
"She had stars on her ceiling, and I always told her I'd lasso them down for her," she writes.
The duet is a testament to Simpson and Nelson's friendship, with Simpson belting, "If you were caught behind those bars / I'd find you in the dark / I feel the lightening every time that you walk by / 'Cause I love your name / Yeah it still gets me high / I'll dance through the fire and you can play it cool / I will be your fool."
"I got your back / I'll be your one true friend / You know you're stuck with me / Until the beautiful end," Nelson sings on his verse. "You can lose your ground / You can lose the fight / When you're on that older road / Drinkin' down the moonshine at night / I'll be on your side."
The sweet track ends with the pair singing together, "I'll give you all my heart / 'Cause that's what real friends do / There's nothin' you can say or do / To make me stop lovin' you / Yeah I will be your fool."
Open Book is available now.