http://edition.cnn.com/2007/HEALTH/0...nce/index.html
In the end, Drs. Fisher and Brown say what they learned from lovers' brains is that romantic love isn't really an emotion -- it's a drive that's based deep within our brains, right alongside our urges to find food and water.
"This helps explain why we do crazy things for love," says Dr. Brown. "Why did Edward VIII give up the throne for Wallis Simpson? The systems that are built into us to find food and water are the things that were also active when he renounced the throne of England."
Very interesting article. It explains a lot about love and rejection and why both affect people so drastically.
Simply put, when you are in love you might as well be riding a cocaine high and when you have been rejected you might as well have someone poking a stick in your eye.
However, read it for yourself... lots of very interesting information there including the difference, in terms of reaction in the brain, between sex and love.