"I can understand how it looked bad to everyone and I'm not OK with cheating," Sara further told 9entertainment.
"What I did was wrong, I crossed a line not telling Tim that I saw my ex and I wish I'd dealt with it differently."
The 29-year-old also confessed she had "major regret" with how she treated Tim when the news came out.
"I regret not sitting there with Tim and telling him how sorry I was. I was just in complete and utter shock and thought, 'How do I defend myself? How do I explain nothing actually happened?'"
It was fellow bride Eden Harper who revealed that Sara had been in contact with her ex-boyfriend. This was after her own groom, Jayden Eynaud, saw a text message from Sara asking Eden to borrow clothes for the meet up.
"We know that they were obviously talking in some way of communication, and we know that they met up," Jayden said during one episode.
"Talking, whether it's call or messaging, that's a form of cheating, and meeting up with your ex-partner behind your husband's back is also a form of cheating," he continued.
"No matter what way you look at it, it's wrong."
As the scandal came to light, Tim claimed that Sara was more concerned with defending herself than how he was affected by her actions.
It all proved too much for the 31-year-old, who wrote 'Leave' during the following commitment ceremony.
Sara, meanwhile, wrote 'Stay' as she was determined to make it up to her husband.
Prior to entering the experiment, Tim split with his girlfriend upon discovering she was unfaithful. As a result, he confesses it takes time to tear down his walls.
Similarly, Sara's ex-partner cheated on her multiple times before MAFS; however the reality star "just kept going back to him".
"Even though it was toxic and manipulative, he had an emotional pull over me and I couldn't help myself," Sara said at the beginning of the season.
Will Sara and Tim be able to work through this hurdle, or will their relationship crash and burn? Here's all we know so far. But stay tuned for more updates.
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