I'll play devil's advocate to an extent and agree that the Bat family and Superman should not be in happy stable relationships. (Largely because the Bat Family are not happy stable people and Superman being married or even in a stable relationship undermines a lot of the "Superman belongs to humanity" angle that they frequently like to play up.)
As far as I'm concerned the rest of the DC universe is fair game.
As far as I'm concerned the rest of the DC universe is fair game.