Jealousy Is Like a Tumor
I don't think jealousy has much of a connection with real, objective conditions. Like if you're fortunate you're not jealous, but if life hasn't blessed you, you are jealous. Jealousy doesn't work that way. It's more like a tumor secretly growing inside us that gets bigger and bigger, beyond all reason. Even if you find out it's there, there's nothing you can do to stop it.
Haruki Murakami, in 'Blind Willow, Sleeping Woman'