each other
Ricardo and Grace are each other because Grace thinks friends are for people who aren’t annoying, and Ricardo thinks Grace is a pain in the ass and refuses to be labeled anything less than a friend.
Grace: 'Why are you still talking to him?' Ricardo: 'Because he’s my friend.' Grace: 'No, you’re each other.'
Ricardo: 'We’re just friends.' Grace: 'You’re each other. You’re not even good friends.'
Grace: 'Why don’t you two just be each other?' Ricardo: 'That’s what we are.'