I came into China with an M type and it expired and I have overstayed for almost 2 years.

But I have been staying with my Chinese gf and we planning to go back to my country to get married this year and come back to China again. But I don't know what to do, am afraid when I exit they will not allow me to comeback in again. Is there a way to to get a clean exit visa without they blacklisting. I need your advise guys