Deryck Whibley and Avril Lavigne

Pop-punk rocker Avril Lavigne and Sum 41 husband Deryck Whibley are separating — but on good terms.

"Deryck and I have been together for six-and-a-half years. We have been friends since I was 17, started dating when I was 19, and married when I was 21," Lavigne, 24, posted on her website. "I am grateful for our time together, and I am grateful and blessed for our remaining friendship. I admire Deryck and have a great amount of respect for him. He is the most amazing person I know, and I love him with all my heart. Deryck and I are separating and moving forward on a positive note."

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Whibley, 29, also commented on the separation on his band's MySpace page.

"It's sad it has come to an end, but Avril and I are still family and moving forward in the most positive way possible," Whibley wrote. "Our decision to part ways is amicable and she holds a special place in my heart and forever will be a great and amazing friend."

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The Canadian couple married in July 2006 on a private estate in Montecito, Calif..