Katie and John, a San Diego bartender and the Season 17 The Bachelorette star's Week 2 eliminee, went Instagram official with their relationship on November 23, only three short weeks after Katie and Blake announced in late October they had split and decided to end their engagement.
Katie, 30, has faced backlash for moving on from Blake too quickly with a "rebound," and manyThe Bachelorette fans have been upset with Katie since Blake admitted in November that he had been "flabbergasted," shocked and "speechless" to learn about Katie's new romance.
Katie therefore posted an Instagram Live video on Friday in response to the trolls and online scrutiny.
"It's hard thing to navigate," Katie said while discussing her "regret" for her "12 Days of Messy" posts, according to E! News. "People are always like, 'Well, you should have told Blake.'"
Katie unveiled John, 27, as her new boyfriend by posting footage of John on her Instagram Story set to Taylor Swift's "Begin Again," a song about falling in love all over again.
The John dedication served as the conclusion of Katie's "12 Days of Messy" challenge in which she had been tasked with matching every song on Taylor's re-released "Red" album to one of her Season 17 bachelors.
Blake called Katie and John "a bomb drop" on him last month and also said on the "Talking It Out with Bachelor Nation" podcast, "I don't think there was any physical cheating there, but there's clearly emotional [cheating] for it to transition as quickly as it did [from friendship to romance]."
Katie confirmed in her Instagram Live that she and John had "talked about" warning Blake about their romance before going public with the news.
"We talked about giving Blake a heads up. [But] here's the thing that people, I think, forget: We're just normal people trying to live normal lives," Katie reportedly said.
"And when have you ever had to tell an ex that you're seeing someone new? And like, how would you tell them that? And would I still have received the same amount of hate even if I did give Blake a heads up? I don't know."
Katie and John therefore decided against reaching out to Blake ahead of the late November announcement.
"All I know is in the moment, I was and am still the happiest I've been and I wanted to make a big, grand statement about where I'm at and who I'm with and that's all I can do is live my truth, live my happiness," Katie explained, according to E! News.
But in hindsight, Katie admitted she probably would've done things differently if she could go back in time. She apparently regrets ever doing the "12 Days of Messy" challenge.
"It wasn't worth it," Katie confessed. "What I didn't like is the amount of people who thought there was no way that John and I could have a connection, that John is so friend-zoned that it's, like, so sad."
John reportedly interjected, "I loved that. That was hilarious."
"I hated it," Katie reportedly revealed, before telling John, "You can love it and that's fine. I didn't like that."
"I wanted to really show that, to me, John is my world," she added. "John is handsome. John is romantic. John is everything. And I wanted to really make a big, grand gesture to show that. Was there a lot of hate that came with it? Yeah."
Given Blake is a wildlife manager from the Toronto area in Canada, Katie and John also pointed out some irony in that John is a dual citizen, both in the United States and Canada.
"I always joke that fate crossed some wires a little bit and got confused on some sh-t," Katie said.
"This is the Canadian I was supposed to end up with," Katie said on Instagram, smiling at John. "No shade. Just facts."
Although Katie never let Blake down gently in regards to her seemingly-sudden feelings for John, she told Us Weekly on its "Here for the Right Reasons" podcast earlier this month that she has spoken to Blake recently.
When asked if she's talked to Blake at all, Katie replied, "Yes, yes."
"I'll leave it at that," Katie noted.
Katie accepted Blake's marriage proposal when The Bachelorette's Season 17 finale filmed in April, but the former couple's engagement didn't air until August on ABC.
In defense of her connection with John and why she had dumped him so quickly on The Bachelorette, Katie shared with an Instagram user earlier this month, "It would have never worked for us on the show. He was too shy. A solid friendship first built an amazing foundation."
Katie previously hinted on social media that she and Blake were fighting too much during their six-month relationship and broke up due to their different communication styles.
The TikTok star and social-media influencer had suggested that Blake was unable to make her happy and vice versa.
John also recently posted a lengthy statement on Reddit to set the record straight on the circumstances in which he and Katie began dating.
"What hurts me... is watching SO many of you build assumptions and throw around accusations based on very limited knowledge of a situation," John wrote.
"Katie and I developed an incredible and deep friendship over the last half year or so. The circumstances by which this friendship formed was a series of crazy, random, and coincidental events, that I'm sure you will all hear about at a later time."
"My point for now, is that we were ALWAYS platonic," he clarified. "Even during my short stint on the season, we never had a chance to foster anything romantic (read as: John blew his chance and left the next day hahaha)."
John suggested that he totally respected Katie and Blake's relationship while they were together for six months.
"The boundaries of our friendship with respect to her ongoing relationship never even required addressing, because it was never a thought in our minds that we would ever be anything more. You guys -- she was engaged," John explained.
"It is apparent that many of you misjudge how both her and I view that commitment. Neither Katie nor I would ever cheat, push someone to cheat, or be involved in cheating."
John insisted it's not in their "nature" to cheat on someone and such behavior "is not acceptable."
"It is not okay. On second thought, maybe this message deserves its own paragraph: There was no wrongdoing prior to the end of their engagement," John wrote.
"Furthermore, I understand that the timeline seems fast and messy. But I urge you to put yourselves in our shoes. Once Katie and I realized there was a romantic connection that we were interested in exploring, we were not starting from scratch; we were building off of the foundation of a close friendship through which, we had already gotten to know each other so well."
John apparently fell for Katie hard and fast once romance became an option for them.
"The speed at which I fell for this incredible, nurturing, and genuinely caring human being was honestly terrifying. I was scared. But every step of the way felt so right," John shared.
"We knew that the only difficult part would be the optics of it all. And that's a sh-tty thing -- worrying about how a natural and organic connection will be viewed by hundreds of thousands of people... when was the last time you had to think about that when you fell for a partner?"
John also recognizes that many The Bachelor fans have disagreed and will still disapprove with how he and Katie went about their new relationship.
"To those of you that suggest we should have waited -- I understand. I hear you," John noted.
"But try to understand what it's like for me, a regular guy, falling helplessly for his best friend, not being able to take her out for dinner because photos would likely leak and everybody would assume we were trying to foster some sort of secret and scandalous relationship haha."
He elaborated, "Our decision to come out publicly was a decision to pursue happiness in the way we wanted. Disagreeing with someone for how they decide to go about it is okay. Everybody is different. I understand."
John said the idea his relationship with Katie was a source of anxiety for anyone "deeply saddens" him.
"As I mentioned before, cheating in any form is unacceptable, and I'm sorry if it looked as though either of us were taking advantage of anyone's trust," John continued.
Speculation Katie and John are dating began swirling in the summer, when Katie posted footage of herself at a bar John works at in San Diego, which prompted rumors John may have been the winner of her The Bacheloretteseason.
Katie proceeded to move to San Diego and continue hanging out with John while Blake traveled to Africa to pursue his wildlife conservation efforts.
Katie and Blake attempted to make a long-distance relationship work as people simultaneously questioned if sparks were flying between Katie and John.
"Internet rumors lead me to this guy becoming a dear dear friend," Katie reportedly wrote on Instagram in September after enjoying a day out with John in California.
While Katie was trying to mend her broken heart in late October, she uploaded a photo of John's dog to her Instagram Story and wrote, "Dexter forcing me out of the house this morning."
Katie had addressed the John dating rumors in early November but danced around an official confirmation or denial.
At the time, Katie shared a throwback video of "the first time I saw John since filming" on her Instagram Story that showed Polaroid photos of the supposed close pals playing cards together, Us reported.
"Y'all getting wild in my DMs," Katie wrote along with a laughing emoticon on November 7.
Blake told The Bachelorette alums Bryan Abasolo and Mike Johnson on "Talking It Out" that even if his split from Katie was "mutual," now he wonders if "he always in her back pocket" and Katie's "Plan B" based on the timeline.
Another reason Katie and Blake may have broken up? An insider told The Sun that Katie's "outbursts eventually became too much" for Blake "to handle" during their relationship.