In pictures published by Mail Online, Jesse can be seen looking cosy with Australian actress Jade Albany, just one day after he was spotted holding hands with Hungarian model Livia Pillman.
"Cara is heartbroken and has completely shut down and not talking to many people," a source tells E! News, adding that while Jesse has not moved out yet, they are now arranging that. "Cara was completely blindsided by the photos of him with other women."
Jesse and Cara announced their engagement in 2016 but had been dating for at least six years beforehand.
"Jesse and Cara have been together for a decade, and have had their fair share of ups and downs," an insider tells E! News. "They truly have been on and off several times throughout the duration of their relationship. Recently, they hit a breaking point and have been having issues."
"It has been very rocky starting the end of last year and especially the last couple of weeks," the source continues. "They haven't been very vocal or open about what they are going through as they are trying to work it out, but they are just not getting along."
Cara's best friend, Olivia Culpo, made an apparent dig at Jesse’s alleged infidelity when she posted a Mean Girls meme of Regina George saying: “Don't cheat ... nobody likes a cheater” to her Instagram account.
She followed it up with another meme of a young Macaulay Culkin holding a rifle in a still from Home Alone.
'When someone upsets my best friend' was written across the top , while also tagging Cara in the photo.
Jesse and Cara have yet to comment on their relationship status.