Dopamine is the "wanting" neurochemical. Endorphin is the "liking" neurochemical. This means you don't have to like something in order to want it. Someone who struggles with an addiction continues to experience desire long after the experience is no longer pleasurable. This is why life's intense pleasures are less frequent and less sustained than life's intense desires.
Read more: Constant Cravings: Is Addiction on the Rise?