A common epithet among lesbians for parents is, "breeders". They reject and contemn family. Whether this lesbian has bought into this outlook (and if so, to what degree), I don't know. Rejection and contempt for family gets complicated when the family at hand is one's own, especially if they've been more or less supportive. So a lesbian with that outlook would find assisting aging parents, even (especially?) if in very ordinary ways, particularly onerous and annoying; complicating this would be the obvious fact that a lesbian with this outlook is a member of two breeders' brood. Again, I don't know if this lesbian shares that outlook, but that she finds assisting her aging parents annoying is suggestive.
Well now, to be fair to the primitive, and assuming she's not lying--and unlike most primitives, the arrows primitive isn't especially known for making things up--she's always come across as eminently credible--her parents are very old, and she has a sister who lives far away.
It's easy to see where the parents lean on her--given their ancientness and her availability--and one's sort of bothered that they seem to be taking advantage of something. The distant sister was probably their desired child, while the arrows primitive, well, she's queer. She naturally chooses to please her parents--or at least satisfy, mollify, placate, them--and the parents use that to the hilt.
It's not good for parents to use, to manipulate, vulnerabilities in a child. It's rather sinister. I was fortunate; I had no such sort of parents. Her eagerness to please, plus the fact that to her parents, she's "less perfect" than the sister and so has to try harder to get their approval, makes the arrows primitive her own worst enemy.
The primitives are very complex people. On the whole, they're simply worthless, sometimes evil, beings one wishes would hurry up and drop dead in the most agonizing painful manner possible, but still, they're much more than that.