well ... i have been with my GF for 7 yrs, most of the time ~5 yrs we have been apart like 1 in north (alor setar) and 1 in south (kl) studying, there have been ups and down, its all depends on how both handle the problem, we got registered on the end of 7th yr, still living apart, until finally done the ceremony 2 yrs later then only stayed together. its depends on trust and the way to solve problem, both must give and take a little, dont mind the tiny stuff, as long as both of you are happy enuf.
ps. my wife too cant get along with my parents even before we registered, so solution, we moved out
there is always a positive solution as long as both think positive of the outcome rather the immediate item.