It's the cognitive dissonance kicking in. I'm very wary in the increasingly rare interactions I have with JW relatives & acquaintances - they would have the exact same reaction ( and have done in the past. ) One of my relatives is very anti & would love to see me DFd.
I've leaned not to avoid talking about JW stuff - in fact , I deliberately bring stuff up ( such as how is so-and-so , etc , or asking about a recent international convention they attended or some non controversial news story such as the building of a new Bethel). I try to simply regard any JW related conversations with a mild interest , as if they were talking about a hobby they enjoyed that I didn't share or their secular job , and try to veer any conversation towards general gossip about JWs that we both know ( which in fairness , most JWs are very good at anyway ) or anything vanilla out of general , somewhat detached , interest rather than anything doctrinal or controversial.
They have kind of learned to play the same game as well - most of them are just social 2nd / 3rd generation JWs without any core beliefs but more into the lifestyle as it is all they have ever known, so it keeps everyone happy. They can always book their time ( and I am sure they do. ) That's not to say that a reaction such as the original poster had won't ever come out - we are all walking on eggshells here and the anger and resentment they have ( and , frankly , I have ) can explode at any time.
The elephant is always there in the room , and always will be , but I've learned to try to manage it so that it is acknowledged to an extent but it doesn't poop all over the carpet.