I originally started thinking about this in response to a crack!ship meme . . . but now I kind of want someone to write it.

Possible scenario (though it's fine to diverge from it): Aredhel avoids Nan Elmoth and wanders into Estolad where the Haladin have settled. Haleth and Aredhel appreciate each other's desire for independence and skill in battle. Once Haleth sees that Aredhel isn't trying to entangle her people in alliances, eventually Aredhel offers Haleth her friendship more successfully than Caranthir did . . .