Megan Fox; Machine Gun Kelly.Photo: Kevin Mazur/Getty Images for The Recording Academy; Alberto E. Rodriguez/Getty Images for The Recording Academy

Megan Fox attends the 65th GRAMMY Awards; Machine Gun Kelly attends the Pre-GRAMMY Gala & GRAMMY Salute to Industry Icons

Megan FoxandMachine Gun Kellyare working on their relationship.

But, the source continues, the actress “is still upset” and “taking one day at a time” when it comes to the future with her actor-musician beau.

“She was never one to casually date,” the source adds. “She is with him because she believes it’s a long-term relationship. She isn’t just gonna give upon their relationship.”

“There are trust issues and this causes conflicts right now. Megan is taking one day at a time,” says the source.

Reps for Fox and Kelly have not responded to PEOPLE’s requests for comment.

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Megan Fox and Machine Gun Kelly.Kevin Mazur/Getty

65th Annual Grammys - Megan Fox & MGK TOUT

Fox firsthinted at a possible breakup betweenherself and Kelly on Instagram Sunday, when she uploaded a post and captioned it with lyrics fromBeyoncé’s 2016 albumLemonade. “You can taste the dishonesty/ it’s all over your breath,” Fox wrote alongside her post, which included photos of herself and a video of an envelope being burned in a fire.

The actress also erased all photos of herself and Kelly from her Instagram page thendeleted her account entirelyhours later.

RELATED VIDEO: Megan Fox and Machine Gun Kelly Haven’t “Called Off” Engagement but She “Took Her Ring Off”: Source

An insider told PEOPLE on Monday that Fox was not on speaking terms with Kelly following a disputeduring Super Bowl weekend.

“Megan is very upset. They had a fight over the weekend andMegan won’t speak to him,” said the insider. And while the pair “haven’t officially called off the engagement,” the source saidFox “took her ring off.”

“They have had issues in the past, but things seem pretty serious this time,” the insider added.

Megan Fox; Machine Gun Kelly.Kevin Mazur/Getty Images for The Recording Academy; Ethan Miller/Getty Images

Megan Fox Machine Gun Kelly

Foxwas absent fromtheSports IllustratedSuper BowlParty on Saturday night, where Kelly performed. However, the pair attendedDrake’sparty together the night beforeon Friday.

Before theJennifer’s Bodyactress deleted her Instagram account, she also followedEminem, who has publicly feuded with Kelly for years. Kelly’s Instagram profile still features multiple photos of him with Fox.

Before Super Bowl weekend,Fox joined Kelly for the 2023 Grammys, where he was nominated for best rock album. After Kelly did not win the award, Fox praised him for handling his loss at the awards show with “a grace and maturity that I haven’t seen from you before” in a now-deleted tribute she shared on Instagram.

source: people.com