Ever since Kanye West interrupted Taylor Swift's 2009 speech at the MTV VMAs, the rap king and pop queen have been at odds with one another.
Swift kicked off her "Reputation" stadium tour Tuesday and addressed the crowd about the longstanding beef.
Read: Katy Perry and Taylor Swift appear to end longstanding feud“A couple of years ago, someone called me a snake on social media and it caught on,” Swift told the crowd, according to The Washington Post.
She continued, “Then a lot of people were calling me a lot of things on social media. And I went through some really low times for a while because of it. I went through some times when I didn’t know if I was going to get to do this anymore.”
Swift said the experience taught her a "really important" lesson.
“That lesson has to do with how much you value your reputation,” she said, alluding to her album title. "I think that the lesson is that you shouldn’t care so much if you feel misunderstood by a lot of people who don’t know you, as long as you feel understood by the people who do know you."
At one point it seemed like the former country singer and West had made up. They were even seen getting chummy in 2015 at the VMAs.
But in 2016, West released his video for "Famous," which included Swift and a gender slur aimed at the singer. She didn't appreciate that and took a stab at the rapper later that year at the Grammys.
The snakes later came into play when Kim Kardashian West, Kanye's wife, released audio allegedly proving the Swift was aware of the upcoming song.
Fans of West and his wife began trolling Swift and her fans.
While the feud between West and Swift may be heating up, the singer did post a happy story to Instagram Tuesday about ending one with Katy Perry.
Swift shared that Perry sent her a package containing an olive branch and a handwritten note.
"So I just got to my dressing room and found this actual olive branch," Swift said. "This means so much to me."
Perry, 33, and Swift, 28, were friendly at the start of their careers, but by late 2013, their relationship had soured. Neither officially commented on what caused the rift, though one popular theory is that it stems from dancers leaving Swift's tour to join Perry's.
ABC News' Lesley Messer contributed to this report.