(OK, in a thread of non-serious replies, 25% of which are by me, here's a serious take...).
In my mind, the substantial difference is that the "victim" placed himself in this situation. I don't mean by initiating or demonstrating interest -- those are objectively good things, because I firmly believe that it's important to clearly express one's intentions in romantic situations. Rather, I mean that the "victim" kept himself in a certain situation: where he continued to express interest but which wasn't reciprocated.
I concede that the wrinkle here is that the woman in question appeared to lead him on, call him by affectionate names, and give off the appearance to, if not being interested, was not obviously uninterested in being interested (if that makes sense; I think it's decent shorthand here).
Accordingly, he either realizes, or should realize, that this is a long-shot gambit.
I suppose I'm assigning responsibility to him for foolishly continuing to pursue that long-shot gambit when he should realize the contours of the situation and understand the odds.