one

ONE is the loneliest number that you'll ever do
TWO can be as bad as ONE.
It's the loneliest number since the number ONE
NO is the saddest experience you'll ever know
YES, it's the saddest experience you'll ever know

Because ONE is the loneliest number that'll you'll ever do
ONE is the loneliest number, much much worse than TWO
ONE is a number divided by TWO (that's easy)
TWO divided by ONE is decided
To bring down the curtain,
then one things for certain,
theres nothing to keep them together.

(Aimee Mann)