After being booed in Milan and when she landed back at LAX, she now has to change her Facebook status back to "single."
According to E! News, Katy was the one who decided to call the relationship with John Mayer off, but there are no further details on what prompted her to do so.
Well, that's certainly one way to squash all of the engagement rumors that have been swirling around the couple.
Things actually seemed to be going really well between the two. They had both been more public about their feelings for each other lately and John even kicked it with Katy and her parents after the Grammys.
We were actually really rooting for these two. They have, however, gone through at least one break-up and make-up before, so we're still holding out hope!