Why Nina Dobrev Was Left ‘Truly Stunned’ on a Birthday Beach Trip to Indonesia (Exclusive)

Nina Dobrev has always been passionate about protecting the oceans — but a birthday trip two years ago left her more motivated than ever.

The actress, 36, tells PEOPLE that the trip to Indonesia she took with a big group of friends — including now-fiancé Shaun White, her longtime BFF Julianne Hough and her The Out-Laws costar Adam Devine — for her 34th birthday two years ago left her “truly stunned in a horrible way.”

“We went on a trip for my birthday to Indonesia, and I had already been to this specific place and I loved it so much that I wanted to bring my friends back there. And when I went back, I was truly stunned in a horrible way at how much the same beach that I’d visited previously — there was no beach left,” she recalls.

“It would crunch every time you’d take a step because there was so much plastic everywhere, of every variety. There was straws and cups and plates and shoes and flip-flops and clothing and everything.”

To make matters worse, Dobrev says all of the trash “obviously it looked North American, and so the fact that it traveled all the way to Indonesia made me really sad.”

“That’s what was so heartbreaking about it. In that moment, [we] immediately started cleaning up the beach. My instinct was to fix it somehow, and everyone around me started doing the same thing and it felt good, but at the same time, it also felt kind of icky. It felt like, it’s just going to get dirty again. It was just going to get piled up.”

The experience left her with more than just a bad taste in her mouth — it made her even more motivated to get involved and spread the word about just how dire the situation is when it comes to plastic waste, so she’s teamed up with SC Johnson to do just that.

“As soon as I heard about this initiative that SC Johnson is doing, it made me really happy and inspired and I wanted to get involved right away,” she says of their advocacy campaign, which uses a video of Zuzu the hermit crab to spur action.

Zuzu’s story — he finds a plastic bottle on the beach and makes a perilous journey to recycle it — “puts a face to this problem,” the Vampire Diaries alum says.

“I feel like that’s why so many people can’t get on board is because it’s sort of out of sight, out of mind. You don’t really see it, but you see it in this film and it really holds you accountable to do something, I think.”

The Join Zuzu campaign is a way to make the problem “really simple,” Dobrev says. “I felt discouraged at that beach, and then when I heard about this initiative… They sort of dumbed it down for us.”

Never miss a story — sign up for PEOPLE’s free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer​​, from celebrity news to compelling human interest stories.

In an Instagram post following her 2023 birthday trip, Dobrev called it “a trip I will never forget” and “a perfect way to start the year filled with so much joy and surrounded by so many incredible souls.”

“Thank you for making me feel beyond celebrated. I love you all. And I feel so lucky to be alive,” she wrote.