Megan Fox is focusing on "her unborn baby" following her split from Machine Gun Kelly

A source told DailyMail.com: "Megan was just done with all of it. She was done with his behaviour and the way that he treated her.

"When she fell pregnant, he thought it meant that she would stay with him no matter what - and it is not the case.

"The most important thing in Megan's world right now is her unborn baby and she has no problem raising the child on her own.

"She's left him before, but this time seems final."

Another insider told the publication the pair's relationship has always been up and down but it hit a low point over Thanksgiving weekend.

They explained: "The way they operate is drama. It's like a never-ending high school relationship. For weeks and months, everything was fine but when they get into fights, it is all or nothing. It took a turn for the worst during Thanksgiving."

Megan announced her pregnancy via a social media post in November.

The Hollywood star - who is already mum to Noah, 12, Bodhi, 10, and Journey, eight, with ex-husband Brian Austin Green - shared photos of her growing baby bump and her positive pregnancy test on Instagram.

Megan and Kelly, 34 - whose real name is Colson Baker - met for the first time on the set of 2021 film 'Midnight in the Switchgrass' - and the actress announced their engagement in January 2022 in a post on social media.

In the caption, Megan - who previously suffered a miscarriage - wrote on Instagram: "In July of 2020 we sat under this banyan tree. We asked for magic. We were oblivious to the pain we would face together in such a short, frenetic period of time. Unaware of the work and sacrifices the relationship would require from us but intoxicated off of the love. And the karma."