In general, my approach to dealing with such people is to stop talking about what's really true, and instead talk exclusively about what experiences I anticipate if I perform various actions.
Talking about your anticipated experiences rather than the Truth is what many people mean by anti-realism.
Sure, I can see that.
Using the language with people that concentrates both of our attention on our actual goals is an example of what I mean by pragmatism.
I mean, if someone wants to discuss ontology and epistemology, that's cool, I'll do that too.
But I'm fairly confident that's usually not what's going on.
From Being a Realist (even if you believe in God):
My mother, who doesn't call herself a theist (I think she's agnostic), doesn't even accept realism. She doesn't even agree with this:
That's little more than tautologies here. Yet it elicited an impression of being forced to believe. I know because she told me about the totalitarian dangers from such narrow thinking.
I'm happy to have finally found the root cause of our ongoing disagreement, but now, how can I deal with that? It looks pretty hopeless, but just in case, does someone have a suggestion, or should I just leave it at that? (My ego doesn't like it, but giving up is an option.)
Now I'm relieved to know that in near mode, she's a complete realist. This craziness only shows up in far mode.