According to my information, there currently exists 1 (one) self help group regarding gilberts syndrome at the moment - in the USA.

Another one is currently being founded in germany (there is some red tape left until it will officially exist).
I will post information about the german one as soon as it was founded.

We do not know anything about asian self help groups or self help groups in other countries (mainly because of the language barrier).

The reason that almost no self help groups exist altough about 5% of the population are affected by Gilberts Syndrome is - in my opinion - the simple fact that GS sufferers are being told that GS is not an illness and has no symptoms. So most people simply never make the connection between their symptoms and GS because they have been told by their wise doctors that no symptom whatsoever can be caused by GS. And if they do a research anyway (which is unlikely, as people trust trust trust "modern" medicine), most people usually stop researching after the first 100 08/15 sites that tell them that GS is not an issue. The people that have internet, of course. Many people dont have internet access or dont use it for various reasons. And of the remaining people only a fraction researches thoroughly enough to find GS internet forums or good GS internet sites that explain the full story. And only a few of them become active members of the GS community and do their own research and try to gather helpful information. And of the ones who gather information there are still a lot who keep the information for themselves, because why should they care for other people who they dont even know? Egoism is very "in" in our "modern society" 
And finally, GS sufferers usually have one problem, the lack of energy...and they have real lives going on, so usually they are lacking energy to do research and exchange information and become active in self help groups...

Well, thats the explanation in my opinion why there are almost no GS communities and for the general "atomization" of individual GS sufferers...other theories are welcome of course