That's probably putting it lightly.
If you don't want to watch Mayer wax poetic about his failed relationship, here's just the Katy quote:
Listen, it was a very private relationship going in. It was a private relationship during and it's a private relationship, still. I can understand asking the question based on some previous answers I have given but I have finally learned how to put the wall between one thing and the other. I've been much happier since then. I'm on the same journey as everyone else. Coupling is a tricky thing.
Source: ellentv.com / via: celebitchy.com