Several of my classmates were homesick when they left the US for medical school. It appeared to me that those who were the *most* homesick were those who:
a) failed to develop friendships or close relationships with others in medical school; ie, they isolated themselves
b) those who had very little experience in traveling (these were also the same people who were very dissatisfied that Oz was NOT the US. As if it should be.
)
c) those with very close-knit families back in the US
and strangely enough, d) those who went back to the US often. Then again,it is perhaps the reason they went back so often. But it never really seemed to help as it seemed as if they lived their semesters just waiting to go back to the US rather than learning about their new home, making new friends, etc.
Being homesick is very natural, especially when living in a foreign land. Fortunately, for those making the Australia-UK-US transition, things are relatively close in being, so that things don't seem entirely different. Moving to Asia can be very disorienting (pun not intended) for the Anglo raised in a Western society.
Learning about your new home, exploring it, reaching out to the natives will help. It will probably be slightly worse than when you left home the first time to go to college (presuming you did) because of the cultural differences. However, it does fade and soon you will find yourself homesick for your new country when you leave it!