It was a whirlwind romance, too.
Diaz's love affair with rocker Benji Madden began in the spring. Seven months later, they're engaged to be married.
Along the way, the actress, 42, was surprisingly candid in interviews on the topic of marriage and children. And the former Good Charlotte rocker, 35, also opened up to PEOPLE – ever so briefly – on the topic of his good fortune. Below, check out the couple's not-so-long-and-winding road to this month's engagement.
May: Diaz and Madden are first spotted together, attending a book launch and then hitting a Los Angeles gym the following day. "They've spent a lot of time at Cameron's house," a source tells PEOPLE. "Cameron seems very happy with Benji. He is the nicest guy and treats her like a lady."
June: The romance goes public, as the couple are seen walking hand in hand around New York City. A source tells PEOPLE that the relationship has "sort of hit Cameron out of nowhere," but that she's incredibly happy – and taking things as they come. "She's at a point in her life where she would love to settle down," the source says. "She's always been open-minded when it comes to men. She just wants to have something in common with them and find a personality that loves life and loves as hard as she does."
July: Madden meets Diaz's family on a Fourth of July trip to Florida. They couple are spotted shopping at Whole Foods and frolicking on the beach, running in and out of the water together.
Later in the month, they take things to the next level with a lavish and romantic European getaway, sailing along the French and Italian coasts on a $633,000-per-week, three-story mega yacht, with friends in tow.
Diaz also gives a revealing interview to Esquire, opening up about life in her 40s and why she might not have children. "It's the best age," she says. "You don't worry about what men think. You just don't worry that time registers anything awful." On the topic of kids, she adds that she was "never drawn to being a mother" and might not want that level of responsibility. "It's so much more work to have children," she says. "To have lives besides your own that you are responsible for – I didn't take that on. ... A baby – that's all day, every day for 18 years."
By the end of the month, it's clear things are serious and there is already speculation about a possible engagement. "It's early, but they have talked about marriage," one source tells PEOPLE.
Meanwhile, Nicole Richie – the wife of Madden's twin brother Joel Madden – gushes to Bravo about Benji's new love, taking credit for being the matchmaker. "I approve of anything that's going to make Benj happy," she says. "I am a devoted sister-in-law."
August: Everyone's been asking Diaz about the relationship, but now it's Benji's turn to open up about it. "I'm really happy right now," he tells PEOPLE, adding that love is the ultimate muse for a musician. "It's same for any man, no matter what they do. It drives you."
October: Diaz arrives at the Academy's Hollywood Costume luncheon sporting a sparkling ring, leading to more speculation about a possible engagement – especially since Madden has moved into her Beverly Hills house. "She can't stop smiling and seems much happier," a source says of Diaz. "They act like they can't get enough of each other and spend a lot of time together. During the days, they often share a workout. At night, they often stay at home and cook."
November: Diaz gives another candid interview, this time to Marie Claire, in which she again addresses marriage and children – and says she doesn't feel pressured by convention on either front. "I'm not looking for a husband or marriage or not not looking for that stuff," she says. "I'm living and not thinking what I should or shouldn't be doing with my life."
She adds: "If a family happens, then it happens. If children come to me, then I would do that, but I'm not someone who feels like she has to do something because it's expected."
December: In her third big magazine interview of the year, Diaz tells Cosmopolitan about her relationship mistakes and the secret to love. "We girls sometimes do the thing where we pick the same person over and over again," she says. "They look and seem different, but deep down, they're the same. And that's on us."
But it sure sounds like she's done with mistakes. "No matter how old you are," she says, "finding the guy who's in the same place as you are and wants to show up is the only way a relationship works, period."
And then, after seven months of dating, it's official: Diaz and Madden are engaged! "It happened a few nights ago," a Madden pal tells PEOPLE. "All of Benji's friends are aware and happy for him."
