there was this quote once that i forget. it's at home! and i'm not. so i'll look it up later.
the hard part about loving someone is that you love them not when it's convenient and not on your timetable, but on theirs.
or something like that.
you just do what you do. whether they love you back or not
really shouldnt have any effect on how much you love them.
i'm sure to some extent everyone uses everyone else, but, how stupid is the Ultimatum.
try, if you deem them worthy.
leave when the feeling is gone, and not a second before.