Jessica pulled a similar thing on Alex at his party I think.
I guess someone taking their life leaves you so powerless that 'blaming them' can happen.. Just like all those people who feel suicide is selfish, because you should think of all the people around you. (Personally not something I completely agree on. Sure it's sad how much Hannah's decision affected most of these people, but in the end 'think about the others!' is not the most convincing argument to somebody who's depressed (as well as probably convinced people are better of without her))