Your Mom sounds like a woman who is not well. She is probably emotionally bankrupt, and truth be known, so exhausted that she doesn't even know how to feel anything. The WTS is not a very loving organization. Sure, they like people to think they are. But they aren't REALLY. Years of being involved and feeling trapped has had to take its toll.
You can't choose for her. But you can choose to be a loving and kind person, no matter how she behaves. You have to consider that she is probably getting "the business" from all her loving WTS friends.
Speaking as someone from the outside of the WTS, I am very turned off by the fact that they expect parents to deny their own children, in order to prove allegiance to a man-made organization. That's enough proof for me that God has nothing to do with the WTS.
Shame on them.