When i lived in Holland i travelled a lot to[and in transit to USSR] to Poland.I met many Dutch guys who spoke medium to good Polish.They only learnt by driving to Poland[and having ‘‘special’’ girlfriends.So if cloggies can learn it there should be no problem for someone like you with a PL girlfriend.Every language has it’s idiosyncrasies.
PS.I never learnt any Polish as it is one of my least favourite countries[together with Albania].