As my buddhist mentor, Daisaku Ikeda, says:
Relative happiness is happiness that depends on things outside ourselves, such as affluence or social standing. While the happiness such things bring us is certainly real, it shatters easily when external conditions alter. Absolute happiness, on the other hand, is something we must find within. It means establishing a state of life in which we are never defeated by difficulties, and where just being alive is a source of great joy.