Cameron Diaz Pens Heartfelt Note to Benji Madden: 'I Never Knew What Love Was Until I Found You'

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You're going to want to have "aww" prepared for this.

Cameron Diaz penned a heartfelt dedication to her husband, Benji Madden, in her new book, The Longevity Book: The Science of Aging, the Biology of Strength, and the Privilege of Time.

"I never knew what love was until I found you," the 43-year-old actress and author writes. "How did I ever live without your love, your friendship, your brilliant mind, your genius sense of humor, and your enormous, loving, beautiful heart?"

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"Thank you for being my best friend, my teacher, my partner in life," Diaz adds. "You inspire me every day with your courage and devotion. Thank you for all the support and encouragement in this book and everything in life. I love you forever and ever."

The couple tied the knot in January 2015 and, back in September, the 37-year-old rocker posted his own sweet message to his wife on her birthday.

"My best friend and everything else -- there's so much I could write. I'm the luckiest guy alive," he said. "I get to spend the rest of my life right here. I love this Woman!! Many more, Baby!!"

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Diaz also opened up about her relationship with Madden on Andy Cohen's SiriusXM show, Radio Andy, saying the first thing she thought when she met him was, "He's hot!"

"We were engaged probably two and a half, three months," she recalled. "It's one of those things where everybody tells you, 'You just know when you know.' And I was always like, 'What does that mean? What does that mean?' Oh, I get it. You just know when you know. You're my husband."

She went on to reveal that now that she's with Madden, she doesn't think about any of her past relationships. "Nothing matters now that I have my husband," she told Cohen. "No one compares. Everything else kind of washes and slips away."

Diaz recently posted a completely makeup-free photo and looked absolutely stunning. See the picture and hear what she has to say about aging well in the video below.