Since then, Diaz, 48, has been reinventing herself — she dove into the world of wellness (writing "The Body Book" and "The Longevity Book"), and most recently became a mom and an entrepreneur. In 2019, Diaz welcomed daughter Raddix with husband Benji Madden, and in July, she launched wine company Avaline.
Diaz says, no matter what she does, it stems from passion, because she can't work really hard on something she doesn't believe in.
"If it's like a burning desire to do so, then I say go for it," Diaz tells CNBC Make It. "Follow that feeling and let it light your way and see where it takes you."
For instance, Diaz and her friend and business partner Katherine Power came up with the idea for Avaline after realizing how many additives were in most conventional wines. The company bills its wine as "clean," made with organic grapes and ingredients that are "free of unnecessary extras" like sulfites, colors, animal by-products or unnecessary sugars, according to the company's website.
At first, "Katherine and I knew nothing about the alcohol industry at all," Diaz says. "We knew nothing about how [making wine] worked, how it was structured or what it would even take to enter it."
Power, who has launched start-ups including Clique Media Group (former parent company of fashion site WhoWhatWear.com), says Diaz rolled up her sleeves and did all the necessary grunt work.
"Cameron is in the nitty-gritty details as one could possibly be as a founder," Power says. "This is definitely not some kind of licensing deal."
According to an Avaline spokesperson, the pair invested their own capital, as well as having outside investors, and spent two years developing the organic wine, which costs about $20 per bottle.
Diaz's wine has faced some criticism for using "muddy" labeling (like calling it "clean") without proper standards. "Despite what Diaz says, wineries are not allowed to add sugar to wine. They can, and some do, sweeten wine with grape concentrates," The Washington Post reported in August. And "[m]ost additives, such as powdered tannins or enzymes that aid fermentation, are natural and benign. Others, like Velcorin, a chemical used to eliminate bacterial faults, are more controversial."
Diaz expected criticism, but isn't paying it much attention. "I do the same thing that I've done my entire career as an actor. I don't read any critics," she says.
Instead, Diaz judges the work she is doing by how she feels about it in the end.
"Intention is everything," she says.
While Diaz says she is enjoying the start-up life, she is most grateful to be a mother. "I'm just really having the best time ever," she says.