Well my suggestions to you is that you do not go for her la...
just because she seldom talks about her bf and her bf is overseas,
you have no right to try and take advantage of her situation and
jio her...
Maybe she just does not talk about her bf, but actually they are
very close. Maybe it is just this period that they quarrelled, and
therefore she seems down and out. Anyway, chinese new year is
coming and i think (if she is chinese and the bf is chinese) then
he would probably be back and they would be meeting up more, that
is when you would feel that you are being "used" and that
sucks.
Dont go for attached girls even if her relationship is rocky or
on the verge of breaking up or the bf is overseas. You should just
be a normal friend to her. No neccessary to tell her you love her
or what, just be there for her and keep your mouth shut. Only when
she is single (in the future, maybe) then you tell her how you
feel. At the same time while being by her side, try not to focus on
her too much and instead if possible look for other girls that are
single.
Your mindset must be right. You cannot keep thinking of her. The
more you think the more you want her to be yours, and the more
impatient you get the more wrongs you do. That is when everything
cock up, and she tries to distance herself from you.
I am also sure, if next time you happen to be overseas working,
and your gf is alone in singapore, you would also not want someone
else to have designs on your gf right?
So, i hope you seriously consider my points here and make the
right choice. There are so many girls out there, look for one that
is truely available. I am sure you can find one.