It's always nice when people bring up your very famous failed marriage in front of a studio audience and the world, isn't it?
We'd expect this kind of shady behaviour from an intern on the red carpet or a foreign language member of the press who doesn't realise how blunt their words are but we really didn't expect this from Ellen.
DeGeneres was playing a 'Who'd You Rather?' game with newly single Perry titled 'Will You Perry Me?', a loose and pretty lame play on 'Will you marry me?', and things got hella awkward when Perry mock-cried about getting married "again" and Ellen rather inconveniently completely forgot about the whole Russell Brand thing.
And just in case you're wondering whether Katy Perry is the type of person to glide over awkwardness and recover gracefully or fall into a deep spiral of cringeworthy squirming when made uncomfortable, it's very much the latter.
It doesn't help that Perry remembers the time Ellen congratulated her on her marriage and gave her gifts, and Ellen does not.