I'm studying oversea, I know some male friend having girlfriend
back in Singapore.
However, some of them have affairs with the girls studying oversea
with them. I personally know 2 of the guys doing this. They pretty
much betrayed to their girlfriends back at home, and good at
concealing the truth too. Some friends realized this (the guys in
particular) but they couldn't be bother about it since its none of
their business.
Funny thing is, the oversea girls knows this, but don't mind doing
it (that the bf have another gf back home) since they also feel
lonely.