If you're really serious about being together, then how about starting again in a third country? I don't know the visa constrictions on Brazilians and HK chinese, but unless your gf has got a great job in HK then would this make sense?
Personally, if you're so serious as to move all the way around the world for her then I think getting married would make sense, you're sacrificing everything for her anyway so might aswell make it official