The Canadian couple wed in 2006, and after that Deryck took "Lavigne" as one of his middle names. Although their divorce has been finalized since 2010, Deryck just now legally dropped his former wife's moniker from his name.
Perhaps it was Avril's remarriage--to Nickelback frontman Chad Kroeger--that prompted the decision? While there's no telling what convinced the "Fat Lip" singer, 33, to go through with the paperwork, the couple's split has definitely not been friendly. Last year, Deryck and his new girlfriend dressed up as Avril and Chad for Halloween--meow!
During their happier days, Avril took credit for helping Deryck kick his drug problem. "He doesn't do drugs. Clearly, he used to, because he talked about it, but I wouldn't be with someone who did, and I made that very clear to him when we first started dating," she told Jane magazine. "I've never done cocaine in my life, and I'm proud of that. I am 100 percent against drugs."