The former TOWIE stars, both 23, were in Marbella for Sam's sister Billie's engagement.

PICTURES: NEW PARENTS BILLIE FAIERS AND GREG SHEPHERD LEAVE BABY GIRL AT HOME TO SPOIL HER IN MOTHERCARE

But sources say that things were so bad between Joey and Sam that he left her there and flew home alone.

Speaking to The Sun, a source said: "Joey and Sam have been on the rocks for a while.

"They are constantly bickering and falling out. It's not been pretty.

"But the last straw was Marbella. The atmosphere between them wasn't healthy and Joey simply had enough - he just had to get away."

READ: BILLIE FAIERS REVEALS SISTER SAM WAS HER BIRTHING PARTNER

While Joey and Sam are yet to confirm or deny their split, Joey did post a picture this week which seemed to show him flying home alone.

The former I'm a Celebrity star uploaded the snap to Twitter on Tuesday, joking about the temperature.

He captioned it: "Most uncomfortable flight and coldest I've ever flew haha. Don't wear shorts and flip flops! Back home in bed :) x"

He might be joking, but Joey is said to be upset by his split from Sam.

READ: DANIELLE LLOYD BREAKS HER SILENCE AS JAMIE O'HARA IS SEEN 'PARTYING WITH OTHER WOMEN'

The source added: "He always thought Sam was the one. It'll take some time for him to get over her."

Joey Essex got back together earlier this year, after breaking their engagement off last June.