My greatest challenge in life - meeting my future in-laws.

I'm meeting up with my gf's parents this coming Sunday. And my heart is pumping like crazy. I don't know what to expect but my gf has been warning me that it might turn ugly. She mentioned about me to them recently, and they weren't too happy about it. In fact, the mother managed to get the father to get on her side. A few days ago, the father told my gf not to go out with me. But she totally ignored him. Bless my gf for defending my honor but I hope things will go smoothly this Sunday. At this point of time, I don't know what to say or do when that day comes. Hopefully, if God willing, they will be kind to me the moment they see me.