you 'MAY' be going away in 4 years and a guy you are seeing says that he wouldn't want to see you too often because he might fall in love with you if he saw you too often and it would be too hard for him to get over you when you're gone 4 years later
I don't get it..uh..what?
It may well be a lame excuse in lieu of telling you that he's really not serious about you, as some are suggesting here.
But... for some guys it could be legitimate, at least per their logic. Let's say he's well established where he is (Brisbane area, right?), with a solid career, home investment, network of friends. He has no desire to ever relocate, happy to remain indefinitely where he is.
Now you come along, and tell him you're just a temporary thing by his time lines, you'll spend a few years with him and then off you go. Why would he invest in a relationship like that? Would you expect him to pull up substantial roots at mid-life and follow you? What if he's looking for a life partner? Why should he take a 4-year detour from his planned path to go up a dead-end street with you? When he hopes to find his partner right there in Brisbane.
One can argue about true love trumping all other considerations. But some guys, especially as they get older (and what's his age?) want both, love and the status quo they've already built. And after all, if you're so definite about relocating in 4 years, can't he also be equally firm & fixed about STAYING where he is in 4 years?
In which case he may be doing you both a favor. You find yourself a transient, while he'll find himself a Brisbane fixture.