Be as nice to her as she is to you, have pity on her for such close-mindedness, and keep her at arm's length. Best you can do, I guess... Though if you could get the opportunity to comment on that with a more reasonable neighbor sometime, the commiseration would probably do you good, and maybe contain her toxicity radius a little bit. But you can't actually change her mind, that's for sure, and lecturing her or "teaching her a lesson" would probably not do any good.
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earth is just a tiny ball