Hades wanted a wife so he asked his brother Zeus to grant his wish for a wife. Zeus offered him Persephone , the daughtero Demeter, but she didn't want to marry him. So, Hades decided to kidnap her and take her to the underworld. When Demeter found out, she became furious. She went to the underworld to find her daughter. Since Persephone already ate some kind of fruit of his so she has to go to the Underworld atleast half of the year to be a wife. So Hades only has a wife half a year every year.