UFC president Dana White said it wasn't just her who was devastated though. Her loyal fan base didn't take the loss too well either.
"When I walked out of the arena, people were crying," White said during the post-fight telecast.
Rousey was criticised in some corners for showing a lack of sportsmanship in her hasty exit, but a cool moment after the fight proves the 29-year-old still cares about those that matter.
TMZ Sports reported a lone fan approached Rousey outside the MGM Grand away from the masses and the pair hugged. Clearly, she's as human as the rest of us.
That's a point Rousey's mum Dr. AnnMaria De Mars wanted to hammer home in the aftermath of the bout that could spell the end of her daughter's fighting career.
In a post on her personal blog, the former judo champion said most average people couldn't wrap their heads around what made Rousey so special.
"All of those who have criticised Ronda for taking a loss so to heart, for not just 'shrugging it off' don't understand that what made Ronda so successful is that she cares deeply about winning to an extent that I don't believe the average person can wrap his/her head around," she wrote.
"Caring deeply about something and working your hardest to achieve it doesn't mean you make the right decisions 100 per cent of the time. Wouldn't it be a nicer world if it did?
"Those of you who want to criticise Ronda ... I know her better than you and she is a smart, kind, talented, generous, hard-working person.
"I am very proud of my daughter. As my other wonderful daughter, Maria, told her: 'We love you just as much 10 minutes after every fight as we did in the 10 minutes before'."
De Mars also had a message for the woman who is no longer the most feared competitor in MMA.
"I would like to see her retire," she told TMZ Sports. "I would have liked to see her retire a long time ago. Who wants to see their kid get hit?
"She's got a lot of talent in a lot of other things ... she's very smart. I told her that at the beginning of this. I said, 'You're smart and beautiful, let the stupid people get punched in the face'."
Despite her wish, De Mars doesn't expect Rousey to make a call on her fighting future straight after an emotional loss like the one she just suffered.
The American's body and ego are bruised, but there is a bright spot for Ronda Rousey fans. After her loss to Holm she admitted she went to dark places emotionally, even contemplating suicide.
But after her most recent defeat, Dana White spent time with her and said she was doing much better than she was after that fateful night in Melbourne.
"I've been with her this whole time. Obviously she's so competitive, she's devastated, but she's a lot better than she was in the Holly Holm fight," White said.
"She was backstage and obviously she's upset, but she's got a lot of support with her and I think it's going to be a lot better than the Holly fight."
Rousey's aura of invincibility that was severely dented by Holm has now been officially ripped apart by Nunes. She's definitely down, but only time will tell if she's out for good.
