Yeah you know that feeling when your ex go with your brother(s) or father instead? It's weird.

Dick sleeps around, but outside the family. He doesn't date Steph or Cass in other media (mainly because they're not even available... who knows if they do maybe they will) and people do reject it when Dick is macking on Catwoman or eyeing Vicki Vale.

Luke and Helena are not close enough to be family so people are cooler with them about family issues.

Their problem is racism.