Kathy can do no right

Even now that they're older, it seems that there is nothing Kathy can do that wouldn't annoy Ruth.  She makes Kathy feel guilty about the fact that she is still a carer.  Ruth HATED being a carer!  She couldn't wait to get her notice for donations, but that didn't matter.  Kathy had something that Ruth didn't, and Kathy was good at it; that's enough to make Ruth bitter towards her.  At one point, Kathy is trying to console Ruth, when Ruth retorts with "'How would you know?  How could you possibly know?  You're still a carer" (Ishiguro, 226).  It's like she can't live if she's not belittling or cutting down Kathy; it's like oxygen to her.  I think, in this instance, part of Ruth's classic hostility towards Kathy is misdirected.  I think She's scared that, when she dies, Tommy wouldn't be very much affected just as Rodney supposedly wasn't devastated by Chrissie's completion.  Either way, I think Ruth is bitter that Kathy has not yet had to shoulder the burdens of being a donor.