Lilly, your father could associate with you and not tell anybody. It's not at all uncommon for JW's to visit churches for weddings and what not, the only counsel they receive is to not tell anybody. (Yes, I'm serious. The elders will tell you to go, just keep it quiet.)
That's probably the best bet, I remember that for the most part anything in a grey area you could do just don't tell anyone. I was told to just go to any concert I wanted just make sure not to make it known that I was that way I couldn't be counselled on it, basically they knew it would stir up a can of worms otherwise. From what I remember Witnesses could talk to their disfellowshipped and disassociated family members they just couldn't talk about JW stuff.