Awks! Taylor Swift, Katy Perry AND John Mayer party together

Imagine having to party not only with your ex, but also with your arch arch nemesis!

Yep, it doesn't get any more awkward than that.

But that's exactly what happened when Drake turned 30 this week and called in some star power to help him celebrate.

The rapper, who officially reached the milestone on Monday, celebrated a day early with a bevy of celebrity guests that included: Taylor Swift, Katy Perry, John Mayer, Jamie Foxx, Shay Mitchell and Zoe Kravitz.

Wait up, whatever happened to that bad blood between Katy, 31, and Taylor, 26?

Not to mention the fact that they both dated John, 39, who also rocked up.

John and Katy dated on and off for years before calling it quits in 2015, while Taylor's relationship with John in 2009 was brief, yet meaningful. At least lyrically anyway...

In fact, Tay Tay was so scorned from the split that she penned her most scathing breakup tune, ‘Dear John’, in his honour.

But it's not the only ex moment Taylor has had this week.

Taylor also performed the song she wrote for her ex Calvin Harris at the Formula One US Grand Prix in Austin over the weekend.

"As a songwriter, the most rewarding feeling in the world is writing something and having a crowd sing it back to you because you know the words," she told the crowd, before launching into a piano-led rendition of her ex boyfriend's song.

RELATED: Why did Taylor and Calvin really break up?
RELATED: Calvin's bestie says Taylor 'was brutal'

"I've never played this song live before, but if you know it, maybe you could sing along, and I could get to know what that feels like, to hear it sung back to me."

Burn!

Since their split in May, it's emerged that Taylor secretly came up with a few lines for the track, but used the pseudonym Nils Sjoberg on the credits.

However, when they separated, stories began to emerge in the media about Taylor's involvement, prompting Calvin to accuse his ex - who'd by then moved on with Tom Hiddleston - of leaking information to steal his thunder.

Admitting she helped him write it, he tweeted, "And she sings on a little bit of it too. Amazing lyric writer and she smashed it as usual.

"Hurtful to me at this point that her and her team would go so far out of their way to try and make ME look bad at this stage though."

Then things got even more personal, with the Scottish DJ bringing her new man and Taylor's enemy Katy Perry into the fray.

"I figure if you're happy in your new relationship you should focus on that instead of trying to tear your ex bf down for something to do," he wrote.

"I know you're off tour and you need someone new to try and bury like Katy ETC but I'm not that guy, sorry. I won't allow it.

"Please focus on the positive aspects of YOUR life because you've earned a great one.

"God bless everyone have a beautiful day (sic)".

Calvin reportedly used Rihanna on vocals, as opposed to Taylor, because neither wanted their romance to overshadow the song.

However, Tay reportedly hit "breaking point," accusing him of being "disrespectful" by insisting he'd never work with her, whilst promoting the track they'd secretly made together.

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