Thank you to everyone for their comments, insights and thoughts, all very helpful.
The difficult personality issues were evident in my husband before PD, but were able to be managed from a relationship perspective, and he could sometimes see them too.
His behaviors were due to a very difficult early childhood resulting in developmental challenges.
However, after 15 years of PD and PD medication, his behaviors and thinking have become extremely rigid.
He thinks his view is the only view of the world and that any different view is deliberate attempt to argue/contradict him and he personalizes every small incident an conversation (if with other people he tells me about the event verbatim afterward and expects me to agree with his view).
I empathize with other caregivers who have a similar challenges - it is not easy.