The only way that I can see someone who is not Australian feeling isolated is if they don't understand the 'culture' of this forum. I'm sure I speak on behalf of 99%+ of the forum members when I say that member location, be it Australian or overseas, has no bearing on how you treat them. The internet is a great way to break down borders and distance!
However, these forums most certainly do have an Austalian nature to them in that the members, while brought together here with a common passion for astronomy, quite often are here simply to socialise and will often post in threads with not only useful information, but with humour, sarcasm, and to use an aussie term, 'just mucking around'
While it is still a valuable resource for the astronomy community, it is also a place where I'm sure alot of people come on every single day to 'spend some quality time' with some chit chat type discussion
Perhaps you have a preconception of what to expect from these forums and because your experience doesn't mirror this preconception you feel isolated?