Moms, hide your sons: Avril Lavigne is back on the market. The early-’00s teen pop sensation is divorcing her husband of three years, sugary pop-punk band Sum 41’s Deryck Whibley. (By the way? Worst. Rock star. Name. Ever!) The pair separated last month, but court papers filed in Los Angeles County last Friday show that “irreconcilable differences” have caused them to split for good.