It's funny that your dad said "unless you are dying." If he really believes the JW crap he expounds then --- YOU ARE going to die ANY DAY AT ARMAGEDDON!!! I recently told that to my mom - I asked her how she would be treating me if I only had a few days to live - say from cancer. I think she would come see me on my death bed. So if they really believe that armageddon is just around the corner - then I suggest they hurry up and say their good-bye's to us now!
On another DF thread - someone posted something that meant a lot to me. It was a reference to 2Corinthians - where Paul talks about making people "overly sad" which led them to satan. It seems he was taking back what he said in 1Cor - to judge and DF people - something Jesus NEVER taught or practiced.
Ask your dad for 1 example of Jesus shunning anyone. Jesus NEVER did it. And tell him that for every scripture he can give you in favor of shunning - you will give him 5 or 10 in favor of love, mercy, forgiveness and grace.