Should not the ryswells be angry for their men butchered at rw? Really Does not lady barbrey care about them? Is she so selfish?

Like the Freys, I think you’ll be quite surprised about what Barbrey Dustin cares about, in the end:

“Night work is not knight’s work,” Lady Dustin said. “And Lord Wyman is not the only man who lost kin at your Red Wedding, Frey. Do you imagine Whoresbane loves you any better? If you did not hold the Greatjon, he would pull out your entrails and make you eat them, as Lady Hornwood ate her fingers. Flints, Cerwyns, Tallharts, Slates … they all had men with the Young Wolf.”
“House Ryswell too,” said Roger Ryswell.
“Even Dustins out of Barrowton.” Lady Dustin parted her lips in a thin, feral smile. “The north remembers, Frey.”