Hey man, I think the answer is very simple and direct. Just let go and move on.
You may hv wasted the last few years of ur time but it is nothing compared to the time that u hv to spend with her till ur death after u hv married her. If ur LIFE partner does not understand what is give and take in life, u better be prepared to give in till ur death if u are gg to marry her. Believe me but u are gg to suffer and live in misery after u marry her. Dun even dream nor expect that she will change after u marry her unless u think u are as handsome as Andy Lau or Aaron Kwok + within the 100 richest man in SG. She has been raised specifically by her parents (by not correcting her) from young to behave in such a manner.
In investment terms, the risk is too high and the gain is too little. Be smart, cut the losses and better start to run now!