Hi loulou,
Delusional disorder is extremely difficult to treat because the person with the condition lacks insight, which means they don't recognize that anything is wrong with them. No amount of reasoning will convince them that their beliefs aren't true. And in many cases, the person with delusional disorder is completely normal in all other aspects of their life, except when it comes to the topic of their delusion. You cannot force them into psych treatment because they cannot see they have a problem, and you cannot prove that they're a danger to themselves or others.
I've read about other people's experiences on a popular psych forum message board devoted to the topic of delusional disorder. So many of these stories are similar. Some people report that the issue was helped when their loved one took certain types of medication; others' stories have never resolved, or have ended badly, after years of coping. In many cases in that forum, the person posting is married to an individual with DD, and also is the object of the delusions.
My own relative's symptoms have gotten worse over time. And she'll talk to me for hours about her delusions. Which is very stressful for me, because she is trying to convince me that another family member is trying to gaslight/hurt/destroy her. This is not true. It zaps so much of my energy (and time!) to listen and absorb her fears (terror) and sadness over something that doesn't even exist. The best thing I can do is simply change the topic when she brings up her delusions. I know this is hard to do when you're living with the person.
