Within the hardwired biological core templates through which they (and all human beings) experience their unique version of "reality" (along with their sense of self and other), nothing changes! Core personalities (including dysfunctional ones) are hardwired-in through a combination of biology, repetition and early-life experiences.
An adult person is who and what they are.
NOTHING CHANGES!
Hi Wanna move on. I couldn't agree more. My ex wife hasn't changed in the 4+ years weve been separated and my exgf is on her second relationship since we split up. Friends and family find it odd how accurately I can predict what they will do. Ive not often been caught out. I even predicted when my exgf would split up from her last boyfriend and was about a week out.
I like the fact that you mentioned biology, repetition and early life experience as I agree that these are the key factors to why they never change.