She sent the same photo to her 20-year-old boyfriend Matt, whom she had been dating for five months. But rather than being excited or flattered, Matt expressed some unhappiness.
Katie then pressed him to explain what was wrong, texting him: "Tell me. Matt."
That's when he responded with a critical text that have led many on Twitter to say that he doesn't deserve Katie.
"You have cellulite on your legs and I hate it and stomach isn't how I like," he wrote. "It's bothered me since I've asked you out. I'm sorry, now I feel like an a**hole."
Without missing a beat, Katie fired back, "Good cuz you are", before saying goodbye. She captioned the screengrab on Twitter with the send-off: 'Boy bye."
Since Katie posted the exchange, it's been liked over 275,000 times and retweeted 50,000 times, and she's had thousands of replies. Many pointed out that Katie's is beautiful and her figure is flawless, while some even tracked down his picture to comment that he's not exactly a catch.
"Lmfao he played himself cause you lookin great," wrote one man. "You're gorgeous, he doesn't deserve you!!" someone else added.
"To all the ladies with cellulite , you cant spell cellulite without U LIT," wrote one more.
Speaking to Daily Mail Online, Katie admitted that this was not the first time Matt had something negative to say about the way she looked.
"He would make comments like he didn't like my make-up and my tattoos, but the text hurt more than the rest of the comments he made before," she said, adding that she broke up with him the following morning because she was "too hurt to talk to him about the whole situation and I felt embarrassed."
During the break-up, she asked Matt why he went out with her in the first place if he was so turned off by her figure - which much of the internet agrees is perfect just the way it is.
"He said he wanted to go out with me still because I had a sweet and funny personality, and tried to avoid [noticing] my weight," she said.
Luckily for Katie, she has more than just the internet on her side - she has her mum and friends, who've been there to back her up.
"[They] were actually the ones who made me realize he doesn't treat me how I should be, especially when I'm so sweet and just want to make people happy,' she said. 'Since he would complain about my appearance from the beginning, I thought it was kind of normal, until I talked to my best friends and mum."