This is a touchy subject so I'll try and keep it as abstract as I can.
Epistemology teaches us that knowledge is limited by perception, and we have, for better or worse, virtually no methods of perceiving what's truly inside another person's mind, perhaps not even our own. So predicating whether person A is or is not "fucked up" on how well they manage to guess what's inside person B's mind is about as asinine as it gets.
You can twist and turn it, but by the end of the day all you'll really do is end up with a reformulation of that age-old conundrum. Anyone pretending otherwise is likely taking some shortcut that won't actually hold up in the general case (and thus possibly lead to horrifying results, depending on the actual concrete context).
Which brings us to the point of something along the lines of 3DPD being actually the sensible way out here, as separating reality from fantasy neatly resolves the issue by simply turning "person B" into now merely "entity B", by relieving it of its capacity of independent thought.