Hades and Persephone
In Greek mythology Persephone is the only child of Demeter, Goddess of nature and earth. Hades is the god of the underworld and the dead.
While Demeter was looking for her daughter one day, she learned that Hades had kidnapped her while she was picking flowers. He had kidnapped her because she was so beautiful that even Hades, the god of death who hardly glanced up at the living world for more then a few seconds, was struck by her, and fell in love with her. Demeter, with her only child kidnapped and forcefully married, fell into depression, and all fertility on earth stopped.
Hades began to notice that his once glowing bride had now become depressed and dark; she only wandered around his gardens without saying a word, looking up at the living world, sighing and sobbing. He attempted to make her happy by lavishing her with thousands of gifts, but Persephone was still unhappy.
Zeus sent Hermes down to to the underworld to demand that Hades release Persephone back to her mother. Hades was truly in love with Persephone and began to panic at the thought of losing her. With a last attempt he resorted to trickery. Before Persephone went back to her mother, Hades approached her with a pomegranate fruit, and began to sob over the fact that she was leaving him forever. He offered the pomegranate as a final present before she left, as it had been grown in Hades’ private garden.
Persephone took the pomegranate from Hades out of pity and compassion, but only ate six seeds from it before throwing it away. When Hermes arrived he saw the pomegranate fall to the ground and questioned Persephone. She admitted to eating it and was told by Hermes that because she had eaten from the garden of death she was forever connected to the underworld and could not leave.
Demeter became outraged that Hades had tricked her daughter into staying and went to the underworld to take Persephone back home herself, but only ended up starting a fight with Hades. To make them both happy, Zeus decided that Persephone would stay with Hades, one month for every seed she had eaten.
Thus every year Persephone would live with her solemn and dark husband for six months and then return to her mother in the world of the living for the other six.
When Persephone is with her mother, Demeter, Demeter is happy and the world goes lush and green, and crops begin to grow. But when Demeter is separated from her daughter, she becomes depressed, and everything on earth dies, animals sleep, and the world freezes in ice and snow.