DSIL's mental health has been poor for years. Over the years DB and DSIL's lives have been steadily constricting.
For example, DSIL's increasing concerns about germs has meant that they've gone from having visitors to their house with fairly normal rules about no shoes indoors, to visitors having to wash their hands in the cloakroom, before going into the living room, to no visitors allowed in at all.
When they married DSIL was phobic about flying, then she became phobic about ships or boats, then she became phobic about driving across high bridges. The area in which they could travel has shrunk and shrunk, meaning they can't visit our other sister, or DB's best friend from university.
I know that their social circle has become very small, I'm not sure how many good friends they actually have any more. They don't have children.
DB has a good job, DSIL of course can't work and hasn't for many years. DB earns enough that she doesn't need to work.
About 8 months ago I had a weird conversation with DB. He said he'd driven an odd route to avoid a road which was badly pot-holed. I said "oh, it's ok now it's been re-surfaced." And DB said, no it hadn't.
I know it has, I was stuck in the queues at the temporary lights while it was being fixed, I've driven along it since.
DB insisted it hasn't been fixed, and said that not repairing it was part of a policy to discourage car ownership. When I said it had been resurfaced he sort of sneered and said I didn't understand the "policy" and tried to explain it to me.
It was baffling.
Anyway, it's happened several times since. DB has described several "policies" that "they" (the council / the government) are pursuing. None of them make sense. Some of the things might have happened due to underfunding / understaffing but he's claiming they are actual deliberate policy and he's doing this tittering / sneering / patronising thing if I disagree or express surprise.
The latest is a secret government policy to try to increase the suicide rate.
He's holding down a good job, I assume he isn't talking about government conspiracies at work.
Our other sister is concerned, too, but she lives too far away to see him often (he can't visit her, and she can't visit him). So she hasn't seen him since I first noticed it. I can only see him if we meet on neutral territory - he can't visit me because we have a dog, which DSIL thinks has germs.
What do I say the next time he tells me about one of these "policies"? Do I try to change the subject? Do I challenge him? Do I tell him he sounds unwell?