I have finally come upon the strategy of dead silence when anything JW related comes up and its been pretty effective. In fact, my dad has told me that my mom recognizes what I'm doing and it frustrates her to no end.
But, the fact is that there can't be a conversation when only one party is talking.
I used to get angry when my mom spoke to me like an outsider that hadn't lived as a JW all my life, but now I force her to deal with me as a non JW and explain all the ridiculousness.
For example, "Dad and I have applied to go to the international convention in Hawaii!"
Me: That's really weird. Why would you have to apply?
Mom: Well, they want to make sure they have enough room for everyone.
Me: (puzzled and incredulous face)
I have learned that this forces her to think about how whatever she's saying really sounds to normal people.