Haven't read it yet but the reason she's given so far to keep the job is a self fullfilling prophecy: keep the job in case they break up/to avoid tension in the relationship (from being dependant on him) but what she gets is tension in the relationship that makes a breakup more likely.
Not that she's the villain; he is exposing himself to risk on his own by being financially and emotionally dependant on complete strangers with a (much) higher likelyhood of being emotionally unstable than the general population. High reward but high risk.