The actress and musician began dating after meeting on the set of ‘Midnight in the Switchgrass’ back in March 2020

Megan Fox and Machine Gun Kelly’s relationship continues to be bumpy, a source close to the couple tells PEOPLE exclusively.

“One day they’re up, the next they’re down,” the source says.

The couple, who began dating in 2020 after meeting on the set of Midnight in the Switchgrass, have previously shared how intensely their relationship started.

“I didn’t know what [love] was until me and her made eye contact,” Kelly said. “That’s when I was like, ‘Whoa,’ ” Kelly (real name Colson Baker) said on The Howard Stern Show back in September 2020. During that interview, Kelly said it was love at first sight, adding, “I did fall in love for the first time.”

In November 2020, Fox said they had a connection of “mythic proportions” and “loving him is like being in love with a tsunami or a forest fire.”

They announced their engagement in January 2022 and sealed their union by drinking each other’s blood.

“That intensity is still there nearly four years into their relationship, but that’s not necessarily “healthy,” the source says.

“There are still a ton of trust issues between them and it’s very toxic,” the source concludes. They can’t stay away from each other and there’s a lot of history there, but they also don’t know how to be in a healthy relationship,” the source explains. “They’ll be totally fine, then days later get into a huge blowout fight and not talk for weeks, but then give in and be all lovey-dovey again.”

Fox, 37, confirmed their engagement was called off some time in 2023 while appearing on the Call Her Daddy podcast earlier this week.

“You got engaged and I think it got called off…how would you describe your relationship with MGK?” asked host Alex Cooper.

“As of now I don’t have a comment on the status of the relationship per se,” Fox replied. “What I can say [is] that [he’s] what I refer to as being my ‘twin soul.’ There will always be a tether to him no matter what. I can’t say for sure what the capacity will be, but I will always be connected to him somehow.”

“Beyond that I’m not willing to explain, but all those things you said were accurate things that have occurred,” the Jennifer’s Body actress responded.

The source confirms the engagement plans were called off.

“They never picked back up wedding plans or even got to a place where they could think about really getting married,” the source said.

“It doesn’t seem like either wants to give the other up, even though they both know it’s not healthy,” the source concluded.

Megan Fox and Machine Gun Kelly Have ‘Tons of Trust Issues’ But Neither ‘Wants to Give the Other Up,’ Source Says (Exclusive)
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Megan Fox attends The One Party by Uber at Fontainebleau Las Vegas on February 09, 2024 in Las Vegas, Nevada.

Megan Fox at The One Party by Uber on February 9
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Megan Fox and Joe Manganiello onstage during the 2024 People’s Choice Awards held at Barker Hangar on February 18, 2024 in Santa Monica, California.

Megan Fox at 2024 People’s Choice Awards on February 18
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Megan Fox attends the GQ Men of the Year Party 2023 at Bar Marmont on November 16, 2023 in Los Angeles, California.

Megan Fox at GQ Men of the Year Party 2023 on November 16
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Megan Fox attends the Medical Inn Grand Opening and Charity Event at Medical Inn on June 16, 2023 in Duesseldorf, Germany.

Megan Fox at Medical Inn Grand Opening and Charity Event on June 16
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Megan Fox attends the Sports Illustrated Swimsuit 2023 Issue Release Party at The Guitar Hotel at Seminole Hard Rock Hotel & Casino on May 19, 2023 in Hollywood, Florida.

Megan Fox at Sports Illustrated Swimsuit 2023 Issue Release Party on May 19
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I have new photoshoots of Megan Fox posing for Sports Illustrated Swimsuit Edition 2023 in the gallery.

Megan Fox ‘Sports Illustrated Swimsuit Edition 2023’ Photoshoots
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Megan Fox attends the 2023 Sports Illustrated Swimsuit Issue launch at Hard Rock Hotel New York on May 18, 2023 in New York City.

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Megan Fox at 2023 Sports Illustrated Swimsuit Issue Launch on May 18
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Megan Fox attends the 65th GRAMMY Awards on February 05, 2023 in Los Angeles, California.

Megan Fox at 65th GRAMMY Awards on February 5
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Megan Fox and Machine Gun Kelly at Vas Morgan’s Halloween Party in West Hollywood, California on October 29, 2022.

Megan Fox at Vas Morgan’s Halloween Party on Oct 29
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