What was the matter with GJ?

One of the various characters in Top of the Lake is GJ, who is somewhat like a leader to the group of women that settled in containers in Paradise, which is also reinforced by Anita when she tells Matt how this whole project started:

GJ, yeah. Oh they met in rehab. [...] Bunny said "You're the first person who's ever really spoken the truth. Wherever you want to go, wherever you want to be, I will pay for it." GJ said "Let us see if you really mean it." and she put her finger on a map. And here we are, Paradise.

And in fact at first she comes across as some kind of New Age spiritual leader and many of the women seem to treat her so and search her advice, in addition to outsiders, like Tui or Robin. This is all fine, except for the fact that GJ doesn't ever do anything at all, let alone anything leading, advising or wise. Rather on the contrary, all she's ever doing is sit in her chair, let the women bring her food and make extremely bitter and cynical comments to everyone speaking to her (oh, and let Bunny's daughter check the internet for gold and stock prices, what the?). And at the end she just leaves with her luggage, having previously searched a flight to Iceland.

So what on earth was the matter with GJ? On the one hand I'd be interested to get a bit more insight into what her character's motivation was and what she actually did at all. Were her advices actually good for anything else than mere cynicism, or was she really just exploiting Bunny and the other women's naiveté? On the other hand I'd like to understand what her purpose for the actual story was? Was this only to undermine the audience's expectations by presenting her as an actual non-leader, like some cynical parody of the usual wise spiritual leaders?

I hope this question isn't too broad or speculative, afterall she might just have been deliberately left an extremely mysterious character. But all the other characters' motivations were largely clear to me (well, Matt's at least partly), while I can't make the slightest out of GJ. So I'd like to hear some well-reasoned theories on her character and its position in the series (or even backed by external information).