I agree that it's irritation with Helen.
She's just starting to move on to a different phase of her life that she has decided to undertake & then is dragged back to trying to sort out Helen's mess-she's once again rushed headlong & not thought it through.
I do agree though that they both treated Bast as a toy.
Just a conversation with someone who they thought was "in the know" & they advise Leonard to act on it, with no thought/realisation at all of how precarious his position is.
Also yes, Henry telling Aunt Juley that they would leave even though she has said no-that is hard to reconcile.
Although he does work, so was it simply a case of then or never?