> This is the only definition that ever made sense for me: Love is that state of being where another person's happiness is essential for your own. I know that I can't be happy without knowing that Amy is, too.

I'll second that definition. That's why I don't use the word "love" casually. I don't love anyone but mrs_bat and our mini schnauzer. I don't love particular foods or television shows. It creeps me out a bit when my mother-in-law says "I love you" just because she's happy I ate the food she cooked, even though I'm sure she really does love me. It's just completely the wrong context.

Call me a cynic, but it seems a lot of people use the word "love" as a synonym for "am related to". They often "love" relatives they don't like. Maybe it's an extension of wintermute's proposed definition, in that they can't be happy unless they do something nice or tolerant for that other person, but to my mind it's much more ingrained guilt and family obligation than actual love.

^v^:)^v^
F"yeah, I love my schnauzer. so what? he loves me too."B