for the first... i wasn't realli given a choice am I? She love
mi no more, even i still do love her? what can i do? not as if i
can stop her from leaving? she is happy, i'm not. This is
life.
for the 2nd, well, i have no idea too, u just have to trial and
error and hope for the best...
for teh 3rd, highly likely. why remain in a relationship when it is
painful... although, i must admit, sometimes pain is addictive...
this is human nature... but generally, if it is painful, everything
will accumulate. and eventually something big will happen... for
teh worse... but if both is able to give and take alittle, then it
isn't realli painful rite? if u find urself always feeling hurt...
well, it is not a good sign...
well, break up always hurts, except for some jerks and some
bitches... but in general, it hurt like hell... well, i guess, u
just have to try not dwell in it, or see/talk to her for a least a
few months... dun let anything remind u of her for the next few
months 
go do something different, treat urself to some goodies, hang out
with long lost friends, go meet more pple... pick up a new hobby
just dun dwell on it
for a least for the moment...