It is really a personal choice but for my view is like
signing-on for guys: Do the BMT first, if u find u are a army
person then sign-on. Dun sign-on liao then find out u are not a
army person then u will suffer inside.
Same logic applies, go wif ur education first, see the work load,
see the if relationship workable or not if u guys decide to get
married then later on + kids. I am not saying it will not work out
but atleast u can gauage what will likely to happen and act
accordingly.
Plus from ur post, ur guy is ready to sign-on (ermm...see my above
first line again) and u urself is not sure if u can "tahan" without
him 
so why not go ahead with each of
ur choices first then see if later on then want to get married or
not.
Well, its just my opinion. 
