Simon Baker Splits from Girlfriend Laura Gibbs After She Attends Anti-Vaxx Protest

The pair first linked in March, just months after the actor separated from wife Rebecca Rigg after 29 years of marriage

Photo: Isa Foltin/WireImage; Laura May Gibbs Instagram

Simon Baker and Laura May Gibbs have split.

A source confirmed to PEOPLE that the Mentalist actor, 52, and activewear designer, 36, "quietly parted ways" several months ago after she attended an anti-vaxx protest. Gibbs has been increasingly vocal on social media about her opposition to the COVID-19 vaccine and recent nationwide mandates for it.

On Sunday, she shared a video while attending a rally in Australia to protest vaccine mandates. The clip shows hundreds gathered and cheering with one person's sign reading: "We stand united against 'no jab no job' and vaccine passports."

Gibbs captioned the Instagram post, "Power to the people ✊🏽❤️ @reclaimtheline."

Gibbs is the founder of luxury fashion and lifestyle brand Nagnata — "the collaborative creation of sister design-duo Laura May and Hannah Gibbs," the company's website states. Last month, she released a lengthy statement from the company's official account criticizing the "discrimination" surrounding the COVID vaccine.

"It is against our personal and brand values to discriminate against any customers from walking through the doors of our Nagnata retail store," the Instagram post read. "In light of the NSW government releasing a roadmap to ease Covid restrictions for the vaccinated only, we have made the decision to close our Byron Bay store from Monday 11th October. We will reopen when ALL are welcome without fear of judgement and fines."

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Baker and Gibbs first sparked relationship rumors when they were spotted frolicking in the waves of Australia's Byron Bay together in March.

The pair's summertime outing came shortly after PEOPLE exclusively confirmed in January that Baker and ex-wife Rebecca Rigg had separated after 29 years of marriage.

"We remain close friends and our three children will always be the most important focus of our lives," the couple, who share children Stella, 28, Claude, 22, and Harry, 20, said in a joint statement at the time.

Simon Baker and Rebecca Rigg. Manny Carabel/WireImage

Baker and Rigg met in the early 1990s and went on to star in the Australian soap opera, E Street.

The actor previously opened up to PEOPLE about his marriage, explaining why he and Rigg never celebrated their wedding anniversary.

"We've never really been big on it. Anniversaries, they're an odd thing, aren't they?" Baker said in 2018. "I think we put too much pressure on it. It's not like that with us. We're a team. Most of the time, 99 percent of the time, we're really great friends. So I don't need to mark it with great things."