HOLLYWOOD - APRIL 02:  Actress Demi Lovato (L) and singer Taylor Swift arrive at the premiere of Walt Disney Picture's "Hanna
Jeff Vespa/WireImage

Demi Lovato caused a whole bunch of hullabaloo when her thoughts about Taylor Swift dropped in an interview with Glamour on Tuesday. In her cover story, she called Swift out for bashing Katy Perry in "Bad Blood" and claimed that celebrity squads (Swift has a pretty infamous one) don't promote healthy body image. Shortly after Lovato's quotes made headlines, she announced she was quitting the music business in 2017.

But this isn't the first time that Lovato has made public comments about Swift. In fact, the two pop singers have an entire history together. Let's take a look at their on-again/off-again relationship:

In the beginning of 2009 (right before Demi's Sonny with a Chance was about to air on Disney Channel), Swift and Lovato were buds hanging out at Los Angeles Kings game at the Staples Center. Friendship!

LOS ANGELES, CA - JANUARY 12:  Recording artists Taylor Swift and Demi Lovato attend the NHL game between the Tampa Bay Light
Noah Graham/NHLI via Getty Images

And in April of 2009, they walked the red carpet of Miley Cyrus' Hannah Montana: The Movie.

HOLLYWOOD - APRIL 02:  Actress Demi Lovato (L) and singer Taylor Swift arrive at the premiere of Walt Disney Picture's "Hanna
Jeff Vespa/WireImage

At the time, Lovato was super close with fellow Disney Channel mate and Princess Protection Program co-star Selena Gomez. They used to make videos together and even had their own BFF spread in People. But over the course of 2009, Swift also got closer to Gomez, solidifying their long-lasting relationship. According to legend, Gomez and Lovato introduced Swift to Joe Jonas, whom she dated in the summer of 2008.

In January of 2010, Demi was signing autographs in London when a fan asked her, "How's Selena?" Demi responded with, "Ask Taylor," insinuating that there was a rift in their relationship. The video, which now has well over a million views, became quite famous throughout the Disney fandom.

Lovato dated Swift's ex and her Camp Rock co-star, Joe Jonas, later that year for about a month.

LOS ANGELES, CA - AUGUST 28: Singer Joe Jonas and Singer Demi Lovato arrive at the 2011 MTV Video Music Awards at Nokia Theat
Christopher Polk/Getty Images

In November 2010, Lovato checked into rehab for drug issues and an eating disorder. In an interview with Access Hollywood, she later recalled that few people reached out to her. Those people were Swift, Gomez and Cyrus. "Taylor Swift sent me an email saying, 'Hey, I don't know if you have a phone right now, but are you okay?"

But then the weirdness kicked back in. Lovato started slightly shading Swift in interviews again. In a conversation with a radio station she said:

"A lot of celebrities don't open up to their fans, they just tell them what they want to hear. They don't really tell them things that can benefit their lives. They just, you know, maybe flaunt around a boyfriend and sell a couple of albums. That's not what my career is about."

Granted, that quote could be about anyone, even Selena, who at the time was dating Justin Bieber. But it seemed fairly pointed at Swift, who became the butt of every joke for her dating life.

In another shady-not-shady quote, she told Company magazine in 2013: "I don't care about Taylor Swift’s love life. I don't care about Harry Styles' love life. I care about mine. I find it weird that people are so obsessed with other people's love lives!"

Both instances could be taken out of context, so when Taylor, Selena and Demi publicized their adorable FaceTime at the end of 2013, people weren't ~too~ surprised, especially because they were spotted shopping a few months earlier.

Selena and Demi had a falling out in 2014, while Taylena continued to slay their friendship. “I think it’s just one of those things where people change and people grow apart,” Demi said when Andy Cohen asked her about why she unfollowed Selena on Twitter in August 2014 on Watch What Happens Live.

That very month, Lovato and Swift looked all buddy-buddy at the 2014 MTV Video Music Awards.

INGLEWOOD, CA - AUGUST 24: Recording artists Demi Lovato (L) and Taylor Swift take a selfie at the 2014 MTV Video Music Award
Jeff Kravitz/MTV1415/FilmMagic

In October of 2014, she told ET Canada that she loved Taylor: “She’s one person that I feel like, one of the few people I’ve maintained a friendship with in this industry. [Fame] just changes people and it’s hard because you have incredible friendships and people change."

At the 2015 VMAs, Selena and Taylor were seated next to each other as Demi performed "Cool for the Summer." Watch Swift's jaw drop as she witnessed the performance.

Then it went dark again. In February of 2016, Demi criticized Swift's decision to cover the legal costs of Kesha's lawsuit against Dr. Luke, saying, "Take something to Capitol Hill or actually speak out about something and then I'll be impressed,” adding, "Women empowerment is taking action now, not when it's convenient." When pressed about it on a fan account, Lovato wrote:

“How the fuck am I making this about myself? At least I’m talking about it. Not everyone has 250k to just give to people. Would love to but I didn’t grow up with money and def haven’t made as much as her. At least I speak up about shit that’s uncomfortable to talk about rather than trying to be politically correct 24/7”.

In an interview with Refinery29 in May 2016, she clarified her Kesha tweets and also explained that she doesn't get along with everyone, especially if they are fake feminists...

“Listen, there’s nothing positive that comes from pitting women against each other. There are women that I don’t get along with, and that’s fine. My thing is, don’t brand yourself a feminist if you don’t do the work. I have an immense amount of respect for women like Lena Dunham...or Beyoncé, who make amazing political statements through their work.”

In July, Kim Kardashian leaked a phone conversation between Swift and husband Kanye West (you remember that, don't you?), which villainized Taylor, who had previously said she didn't give Kanye permission to use his "Famous" lyric. Among the backlash, which included the #KimExposedTaylorParty on Twitter, Demi faved a tweet read, "I LOVE KIM KARDASHIAN."

Also in July, Calvin Harris went on a multi-tweet rant about Swift's character after their public breakup. And guess who followed Harris on Twitter shortly after?

That's all for now. Watch a throwback Fuse interview with Lovato below: