LOS ANGELES >> Jessica Simpson, the pop singer turned fashion mogul, reality TV star and bestselling author, is returning to her musical roots.

Simpson released “Use My Heart Against Me,” a single off her upcoming EP, “Nashville Canyon, Part 1,” last week. It marks Simpson’s first single in almost 17 years — her last project was the 2008 album “Do You Know.”

In an interview for the Cut with her sister, Ashlee Simpson Ross, the 44-year-old musician said she’s exploring a new chapter in her life through music. “Through the deepest heartbreak of my life, it was the most intense yet enlightening therapy I’ve ever been through.”

In January, Simpson and former NFL player Eric Johnson announced their separation after a decadelong marriage. Together, they have three children: Maxwell “Maxi” Drew, 12; Ace Knute, 11; and Birdie Mae, 5. Their $18 million Hidden Hills mansion was listed for sale days before the news broke.

Simpson said she first came up with the idea for the rockabilly EP when she was in Nashville, Tennessee, celebrating her daughter Maxwell’s birthday. Instead of requesting the Happy Birthday song, the 11-year-old asked her mother to sing Hank Williams’ “I Saw the Light.” Simpson said it led to “all these flashbacks of making [her] first record at 14.”

“I saw the light: I had to be in Nashville,” she told Simpson Ross. “I started looking at real estate that day.”