Mariah Carey and James Packer
Mariah Carey and James Packer split after a fight on their Greek holiday in September Lucas Jackson/Reuters

Bryan Tanaka received a "big reality check" as he spotted his girlfriend Mariah Carey and her former fiancé James Packer hitting it off on Sunday's episode of Mariah's World.

According to E!News, Tanaka said it ''f*****g sucks'' after he spotted the former couple get ''touchy feely''. Australian business tycoon Packer appeared on the show to watch Carey's performance.

"Seeing Mariah and James connect is super weird for me because I haven't really seen it before. I feel like I've been living in this fantasy for a while and all of a sudden this is like a big reality check," Tanaka said.

On Saturday, Carey and the back-up dancer were spotted at London's Dorchester Hotel, where the songstress performed at a wedding.

Earlier, during Dick Clark's New Year's Rockin' Eve show on 31 December, Carey had abruptly ended her performance as she suffered technical difficulties on stage.

At the time, Carey's former husband Tommy Mottola defended the singer.

"My only advice is that she should hire more seasoned and respected professionals to surround her and help her with her career! I would never have encouraged her or guided her to do something like a reality television show!!!!! I don't get it!! That does absolutely nothing for her integrity, her credibility, or her massive talent!!" Mottola told Page Six.

"Most certainly none of these issues or problems ever existed with her in her early days at Sony for the first 10 years when she skyrocketed to global superstardom!! Where absolutely meticulous and methodical attention was paid to every single detail and nuance that went on into her career!"

Mottola and Carey were married between 1993 and 1998.