<human>: Provide a brief overview of the text.

I was recommended to cross post from /r/advice. My dad is ill and has been prepping me for his eventual demise, signing over titles, giving me security codes to his storage, etc. He has some concerns regarding his estranged wife's behavior after his death, which is valid since she is unstable and has ill will toward me and my family.
Some background on his wife, she has a severe prescription drug problem coupled with bipolar disorder. They have been married for about 6 years but 4 of those years they have been separated, my dad has tried divorcing her and has been met with physical abuse as well as her calling the cops claiming that he hit her which resulted in him spending 4 days in jail, there was an altercation but it was one sided, my father has never and would never hit anyone he is weak and ill and does not have the strength to. She has financially drained him of almost all his assets and savings which leaves him trying to live off of meager social security checks and can no longer afford the legal battle of trying to cut ties with her. She does not like me, his only daughter, for unknown reasons. She claims that I am stuck up toward her and is greatly offended by my personal success. She threatened to bring a gun to my wedding also threatened to poison me while I was pregnant. I have a no contact order against her.
How can I prepare myself legally, mentally, and physically for my father's death and having to deal with my vastly unstable stepmother?  I live nearly 4 hours away and I'm mostly worried about sentimental artifacts, my father's dogs, and her ability to act like a sensible adult and not go to his house after his death to destroy everything out of spite, which she has done before for other reasons. Thanks!
<bot>: I'll father's estranged wife is threatened to create a mess of things after my dad's death. How do I protect myself and my father's stuff? Is there anything I can do legally to keep her from his property?