"I cheated on my ex-[girlfriend] but I can vouch firsthand that I tried to walk away from the relationship several times but she wouldn't let me go," Amanda explained.
"I obviously made that poor decision to cheat on her [and] it hurt her obviously in the process but I understand what its like to be on the other end of it," she continued.
She added: "I understand that good people make bad choices every now and then."
"Two people play a part in a relationship so it's like what have you not done to have let that partner stray."
The strength coach is set to be matched up with Tash Herz, 31, on the upcoming season of the Nine show.
In a promo, Amanda is seen in tears as some of her loved ones refuse to show up for the show's first ever same sex wedding.