In Riders to the Sea, why does Maurya try to dissuade Bartley from taking the rope? Why do the girls send Maurya after Bartley?

Maurya tells Bartley that once Michael's body has been located, she'll need the rope to help lower his coffin into the ground. That's not the real reason, however; Maurya, ever mindful of the weather conditions, has noticed that the wind is rising from the south and west, potentially endangering Bartley's imminent journey.
But Bartley is insistent on going and on taking the rope with him. He says that he needs the rope as a halter for the red mare he's planning to take with him to the horse fair along with Michael's gray horse. There won't be another fair for a fortnight, so Bartley has no time to waste; he and the horses must head off as soon as possible.
Bartley leaves for the boat in such haste that he leaves behind his bread. Cathleen urges Maurya to go out and give it to him. Not only will he then have something to eat for the journey, but Maurya will be able to wish him godspeed, as she pointedly failed to do when he left the cottage. Cathleen believes that Maurya's wishing Bartley godspeed will break the curse of her not having said it the first time.