After speaking among her fellow recruits about feelings of anxiety, Bonnie later made the choice to quietly leave the program.
"It's just a lot. It's kind of a bit traumatic for me," she told Bra Boy Koby Abberton while toying with the idea to walk away from the show.
"I've never felt anxious, but holy s--t. I don't feel good. I'm always stressed and I'm just feeling really s--t."
Bonnie eventually told DS Ant Middleton that she wanted to voluntarily withdraw.
"I'm gutted that you're going," Ant told Bonnie, before the pair shared a hug.
"Now you can go and inspire others, and inspire yourself to be a better version of who you are - which I know you have been on this course."
Olympian Kerri Pottharst may have been the oldest recruit on SAS Australia at 55, but the sporting legend proved age is just a number when it comes to pushing through gruelling challenges.
Unfortunately, an old knee injury reared its ugly head, with a tear forcing Kerri to withdraw from the program.
"I can't do this. My knee has given out," she told directing staff Ollie Ollerton after the brutal ice bath challenge.
"I'm done. As much as I want to be here. My body said no."
When the recruits were made to fight each other in front of the group, some were left shocked over how intense the brawls would become.
Tennis star Alicia Molik chose to hand in her number after retreating from the onslaught of Jana Pittman’s punches in a brutal bout.
"Don't turn your back! Face your target!" the DS was heard screaming at Alicia as she tried to protect herself from Jana's punches and her shocked recruits watched on.
"I just got scared," said Molik. "I thought I’d be a good fighter. I tried my best."
During a savage fight with Mark Philippoussis, musician Pete Murray fell and dislocated his elbow, a serious injury which left him with no option but to be medically withdrawn from the course.
"I've only had a couple of fights in my life but they've been defending other people," Pete said. "So I don't get in a habit of getting into fights. You just don't know what's going to happen."
The singer also revealed it took three attempts to put his elbow back into place.
"I didn’t expect to go out like this," said Murray. "I was getting flogged, I couldn’t get close to him."
But despite the expected turn of events, Pete remained positive.
"I can walk away from this knowing I've done the best I can. I've pushed myself as far as I can and as hard as I can. If I've left nothing on the table then I've got to be happy," he continued.
The former politician made a tearful exit as she realised the extent of her calf injury was going to hold her back in physical challenges.
Claiming that her head and her heart wanted to stay more than anything, Emma made the call out of fear of holding the rest of the recruits back.
“I’ve had some complications to my rehab with illness, I’m still not running properly or back on the court,” Emma explained on Instagram.
“And I’ve got unfinished business with the course. 😷 Will I be back?” she teased.
The celebrity chef decided he was out when tasked with sitting in a submerged van below water for 40 seconds.
He stood up, handed in his number, shook the DS’s hand and walked off.
“I came on this course to prove something to myself, and I’ve just realised I don’t need to prove anything,” he said. “I’ve got a f***ing good life, and I want it back.”
With the daunting nature of that challenge at play, we can’t say we blame him!
Model and TV presenter, Erin Holland, became the second recruit to voluntarily withdraw during a gruelling combat drill.
As punishment for doing a part of the drill incorrectly, DS Ant Middleton had the former Miss World Australia carry actor Dan Ewing on her back as punishment - something Erin visibly struggled with.
As she continued to struggle amid exhaustion, the rest of the recruits were punished by having the drill extended, leading Erin to call it quits as she grappled with guilt.
"I can't do it to them," she told Ant as she removed her arm band number and voluntarily withdrew.
Erin later revealed on Instagram that she was "gutted" over leaving so soon.
"Gutted my time on @sasaustralia came to an end so soon. I had all the heart & head, but lacked the body to see it through," she wrote.
"It’s so hard to see myself so vulnerable, but if this course has taught me anything, it’s surrendering to the pain & learning how to fail with grace."
The season's premiere saw socialite Brynne Edelsten voluntarily withdraw just six hours into the program, citing a knee injury for her exit.
Forced to perform an exhausting exercise that's rightfully dubbed a "beasting", recruits were made to hold themselves up in a push-up position while still wearing their 20kg backpacks.
It was at this point that the 38-year-old admitted defeat and voluntarily withdrew.
"I've lived a very high life but there's also times where I've struggled so I'm mentally strong but I don't have physical strength," she said after quitting the show.
"Even though I'm disappointed I'm leaving I know I need to because my body is not strong enough to be doing these things but I have no regrets about this. If anything it encourages me to work to see what I can do in the future."
Brynne also admitted that the show was by far the "toughest" challenge she's ever taken on.
"This is definitely the toughest thing I have ever attempted. I thought I was in pretty good shape until that first day when I realised that physically, I don’t stand a chance of completing the course," she said.
SAS Australia continues Monday, Tuesday and Wednesday at 7.30pm on Channel Seven.