The actress says after having her second child, she understood what others have gone through

Drew Barrymore opens up about the lessons she learned throughout her troubled childhood and how she finally found her happily ever after. Subscribe now for this exclusive interview, only in PEOPLE!

Being a mom is everything to Drew Barrymore.

Her life with her two young daughters, Olive, 3, and Frankie, 18 months, and husband, art consultant Will Kopelman, 38, is “is an abundance,” she tells PEOPLE in this week’s cover story. “It’s perfect and totally imperfect.”

Yet after Barrymore gave birth to Frankie, she sensed something might be a little off. “I didn’t have postpartum the first time so I didn’t understand it because I was like, ‘I feel great!’ The second time, I was like, ‘Oh, whoa, I see what people talk about now. I understand,’ ” she says. “It’s a different type of overwhelming with the second. I really got under the cloud.”

Between work — her new book, Wildflower, hits shelves Oct. 27 and her next film, Miss You Already, hits theaters next month — and motherhood, Barrymore, 40, felt pulled in every direction.

“I just got right on the idea of, where do I need to be the most? Fifty-fifty would be ideal but life doesn’t work like that. Life is messy,” the actress says. “It was just really challenging and I felt overwhelmed. I made a lot of decisions and I definitely changed my work life to suit my parenthood.”

Drew Barrymore postpartum depression

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While her postpartum was “short-lived, probably six months,” Barrymore is grateful for the experience, which constantly reminds her to stay present in the moment.

“It’s really important. I was in the kids’ class with Frankie and Olive this morning and I started fretting about some piece of work news that was just stressful,” she recalls. “You know, in like the Broadway Babies class and it’s the one-hit wonders day, and they’re singing I don’t even know what song, and we’re all doing our lollipop drums and I just thought, ‘Save it until after class.’ One thing at a time.”

Drew Barrymore motherhood Wildflower

As the creator of Flower Beauty, Flower Eyewear and Barrymore Wines, the actress says it’s important to her for her daughters to see her working as a good thing.

“Putting a negative stigma on work is a go-to. It makes us feel like it proves to our children that we don’t want to work, we’d rather be with you,” Barrymore adds. “I want them to see that work can be a good, positive, fun, happy thing. I’ve worked since I was 11½ months old so I have to be able to work, too. But I have to put them first. I don’t know if it’s good enough for anyone but I’m doing my best.”

Drew Barrymore people cover

For more of our exclusive interview with Barrymore — in which she reveals her own memories of childhood and the happiness she’s found as a wife and mother — pick up this week’s issue of PEOPLE, on newsstands Friday.

— Julie Jordan