1
general::
Spend the rest of one's life in happiness, as in In her romantic novels the hero and heroine end up marrying and then live happily ever after. This hyperbolic phrase ends many fairy tales. [Mid-1800s]
American Heritage Idioms
2
general::
Phrase(s): live happily ever after
Cliché to live in happiness after a specific event. (A formulaic phrase at the end of fairy tales.) • The prince and the princess lived happily ever after. • They went away from the horrible haunted castle and lived happily ever after.
McGrawhill's American Idioms And Phrasal Verbs