A need or a want?

A friend just brought up a question about relationships
In this point in time, is it a need or a want?
the argument was that
if it was a want, that we would not make the necessary compromises to attain it
but if it was a need
it's something one cannot live without
it's more than a question of just missing someone and wanting to see them
its more a life and death situation in a way of saying...
then we would do anything for it

How would you know if it's a need and not a want?
They both have the same symptoms
how does one diagnose a situation like this?

Its a matter of severity, I guess
you can live without something you want
but not without something you need
a want is a passing fancy
a need is forever

A want does not mean you don't love
just not enough
not enough to be willing to take risks for

A need, you will do anything for
leap from a plane or dive in the deepest oceans.....