Is There a Mathematical Formula for Replaceability in Relationships?

[dianm]

I'm looking for a formula to represent the idea that if I didn't have you, someone else would be equally nice or better.

Suggestions?

Thanks,
Dian

 

[CompuChip]

$$\not\exists u \implies \exists x, x \neq u, |x| \ge |u|$$
Something like that?

Yay for metamathematics :)