Maybe, just let this one go. We all have our hypocrisies and we all have to do whatever we can to get through the day. Christians would call it "grace" in your not challenging her on it.
However:
Encourage her to identify the things she wants to change and work to change it. Results are what she wants, not just the positive thinking-but the WT drones have been doing, doing, doing for over a century and have nothing to show for it. Show her how REAL productive activity has good results-and she can soon see the pointlessness of her unproductive busy work. We know as JWs that they will stick to an action or thought DEVOTEDLY. We also know that they will get nothing out of the WT corporation. Help her accomplish something real and don't address the magical thinking. Just let that be. Positive thinking won't hurt if she couples it with positive and PRODUCTIVE activity.
I'm just avoiding any kind of deep anything with my mom, she drives me batty. But she is my mom and I love her, so we need to find a peace. I keep trying to avoid all the tough things and it gets insane sometimes, but it isn't without value to work at peace even when we don't get along on some (or most!) issues. Sometimes peace means that we let things go that don't actually matter.