Fox appeared without her engagement ring at the party, as she debuted a new vibrant red hairstyle along with her fresh-off-the-runway, plunging Miss Sohee Couture gown.

“She seemed really happy and light. Super nice to everyone,” an insider says of Fox inside the party.

Another source tells PEOPLE Tuesday that Fox and MGK are still working through relationship problems.

“They’re not completely done. They’re still trying to sort through things, but most of their friends think it is likely over. They’re just not ready to totally call it yet,” the source says.

Megan Fox and Machine Gun Kelly. KEVIN MAZUR/GETTY

Fox’s solo appearance following the Oscars ceremony comes about three weeks after an additional source told PEOPLE she and Kelly are “still not in a good place,” even as she returned to Instagram and shot down rumors about their relationship.

The actress had completely deactivated her Instagram account in February after hinting at a potential breakup between her and her musician fiancé, but she shared a since-deleted post upon her return to the platform saying there was no cheating involved in the relationship.

“There has been no third party interference in this relationship of any kind,” Fox wrote. “You need to let this story die and leave all of these innocent people alone now.”

A source who is familiar with both Fox and Kelly told PEOPLE in February that the Transformers actress had initially suspected something was amiss and reacted out of emotion.

“She’s now posted that there was no cheating, but she initially thought there was and now is backtracking a bit,” the source says. “She was definitely hinting at infidelity with her first post. She regrets making it all so public, but was really upset in the moment.”

“Their relationship is crazy and intense,” the source added at the time, “yet it wouldn’t be shocking if they were back together completely by the end of the week.”

Fox had sparked rumors when she hinted at a potential split when she uploaded a series of photos of herself and a video of an envelope being burned in a fire pit in February. She captioned that post with lyrics from Beyoncé’s 2016 album Lemonade, writing, “You can taste the dishonesty/ it’s all over your breath.”

Fox and Kelly first met on the set of the indie thriller Midnight in the Switchgrass in March 2020. The musician proposed to Fox in January 2022.