What is Love?

I've been falling in and out of love quiet some times in my life so far. And everytime i was sure at the start, that this time it was for real, that it was really B.I.G. L.U.V.  Unfortunately it always turned out to be something else, and i found myself alone again in the end ...

How can it happen, that we confuse a holiday romance with the "real deal"? Or that the people we love the most hurt us the most? Or said with the lyrics from one of my favorite songs : "First it's milk and honey, then it's so much money and in the end - you just wanna go ..." (from "Wonder" by Butterfly Jones). And after every loss on the battleground of love, why do we still keep our eyes on the horizon, looking out for someone to give love, get love?
What is this so called love? Is it a sort of drug? A (confused) state of mind? An illusion? The impossible dream? What's the essence of the central motivation of mankind next to greed?

What are your thoughts and believes about love?