Sierra broke her silence on the coupling during an Instagram Q&A, and questioned whether it’s a publicity stunt.
'I actually only found out about this yesterday, and to be honest, I was really shocked,' Vanessa said.
'I'm not sure if she genuinely likes him or it is more for publicity? Not going to lie, when I found out I felt sick to the bone.'
Rhyce and Vanessa were involved in a messy split earlier this year.
The former couple is believed to have split in March after she alleged that the controversial tradie— who briefly appeared on MAFS— assaulted her at a fitness camp in Thailand.
As previously reported, Vanessa cut the trip short and headed back to Australia to file for an intervention order. Under the Victorian intervention order, which is similar to an apprehended violence order (AVO), the Perth-based carpenter is banned from contacting Vanessa.
Earlier this year, she spoke out about the alleged abuse, posting an Instagram of herself with what appeared to be a black eye.
"7 days of isolation and I’m back to myself again. Those closest to me already know what happened. This was taken the day I left and it does not even hint the extent of what I went through."
Vanessa continued: "Domestic violence isn’t a f****ing joke, so here is (literally) a taste of your own medicine. On a completely separate note, @rhyce_power how is Thailand?"
Rhyce later denied the allegations in a lengthy Instagram post back in April.
"There's always two sides to every story, and everyone needs to believe that," he said. "Everyone's jumped on the bandwagon without even hearing my side of the story - which I understand - if a girl makes an allegation about a claim [sic], whether it's an attractive girl or any girl, everyone's going to jump on the bandwagon, and I fully understand that."
Yesterday, Rhyce and Tamara— who were laying in bed together at the time— addressed dating rumours, sarcastically revealing, "No, we aren't a couple. We're both single. We're friends hanging out with each other in bed, watching movies."
WATCH: RHYCE AND TAMARA GET COSY IN BED TOGETHER