If that question was in good faith, I think your response might be the right one. But I very much doubt that question was in good faith - it sounds more to me like "suck it up or get out, princess".
Regardless of the intent, the response is incongruous to the prompt.
A: This is the job; take it or leave it.
B: You don't really want me to leave it.
Maybe A does or doesn't want that, but how does that have any bearing on B's decision-making? Let's call a spade a spade. The nurses who are not quitting are doing so because (they think) the job is still good; it's just not as good as it was a few years ago. The nurses quit did so because (they thought) they could get a better deal doing something else.
