Megan Fox, Machine Gun Kelly 'Slowly' Reconciling — But Wedding Planning Is 'Halted': Source (Exclusive)

Megan Fox and Machine Gun Kelly still have a long way to go before they're fully back on as a couple, a source tells PEOPLE.

"They are slowly working on reconciling but he's totally in the dog house still," the source says about the rapper, 33, who showed up to the Sports Illustrated Swimsuit issue launch Thursday night to support his cover-star fiancée, 37, though they did not walk the red carpet together.

Says the source, "He's doing whatever he can to get her back, and she's making him work for it. It's still an unhealthy dynamic though, and their friends just don't see this lasting."

Additionally, their wedding planning "remains halted," according to the source.

"He has a lot of proving himself to do, and he doesn't want to give her up. He is great with her kids and super hands on. It's a work in progress," the source adds.

Reps for MGK and Fox did not immediately respond to PEOPLE's requests for comment.

The Jennifer's Body actress and the "Bloody Valentine" musician (aka Colson Baker) met while making the movie Midnight in the Switchgrass in 2020; they got engaged in January 2022.

Fox hinted at a possible breakup this past February, removing photos of her fiancé from her Instagram account and posting a cryptic caption. A week later, she returned to Instagram to break her silence amid speculation that their relationship might be over.

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"There has been no third party interference in this relationship of any kind. That includes, but is not limited to...actual humans, DMs, AI bots or succubus demons," Fox wrote at the time.

By late March, a source told PEOPLE Fox was continuing to not wear her engagement ring and that they were in therapy to work on their differences. But, the source said, Fox was "having a hard time trusting" MGK.

Fox said on the Give Them Lala ... With Randall podcast back in 2020 that she felt an instant connection with MGK when they met and began working together.

"I knew right away that he was what I call a twin flame," she said at the time. "Instead of a soul mate, a twin flame is actually where a soul has ascended into a high enough level that it can be split into two different bodies at the same time. So we're actually two halves of the same soul, I think. And I said that to him almost immediately, because I felt it right away."