I have several people like this in my family and it is heartbreaking. The core of their condition is that they reject all the (considerable!!) care and help and love and support offered, making it completely impossible for anyone to help improve their situation, and then they will lash out violently (often physically) because they feel nobody cares enough. Often post on social media - crying photos and videos about how utterly alone they are in the world and how they’ve been abandoned and betrayed, when actually about ten of their closest friends and family have been entirely financially supporting them for decades, advocating with doctors on their behalf, coming and staying with them and helping them to eat, finding them therapies (that they won’t engage with in good faith or at all).
I’ve eventually gone NC as the alternative was to be bled completely dry emotionally, financially, and practically - and still never be perceived as doing anywhere near enough to help them. The more we gave the more tirelessly they would work to perceive us as abandoning uncaring arseholes. That is the dynamic unfortunately with many people who are extremely severely affected by this condition.
it is different for people who are less severely affected - which is why I think we need different terminology for those with EUPD diagnoses who have insight and lower care needs and are able to live independently, and those who really do need the on-call support of an interprofessional team.