The whole idea that Harley has to leave the Joker needs to be abandoned. If DC wants a hipster, animal loving, anti-hero, abuse survivor, lesbian character that lives in Coney Island they should have made a new one because that’s not Harley. 

Harley is the girl who is crazy enough to love the Joker. She’s the one who was liberated and empowered by the Joker. She was cute, childish, adorable and madly in love and seemed so innocent but could turn deadly in a second. Her love for the Joker is what drove her insanity. 

She belongs with the Joker. End of story.