She has a cover story in the magazine this month where she talks about dealing with Lyme disease, a potentially chronic bacterial illness. The Canadian singer experienced mild to moderate symptoms for months before things came to a head while she was celebrating her 30th birthday in Las Vegas.
Ultimately, she was bedridden for five months.
"I thought I was dying," she said. "I felt like I couldn't breathe, I couldn't talk and I couldn't move."
At times, the "Complicated" singer said she would go an entire week without having the energy to shower.
Lyme disease can be difficult to diagnose, and the symptoms sometimes don't appear until long after you've been bitten by a tick carrying the bacteria. Lavigne asked her fans to pray for her last year when she was trying to figure out what was wrong with her. She also rebutted rumors that "health issues" was code for "rehab."