he proudly voted for Donald Trump every time he ran and never hid his political beliefs from his family.
This sounds like an extremely euphemistic way to say he would not shut the fuck up about Donald Trump and his political beliefs. And his family likely gave him every chance in the world to quit that shit, and when they eventually just stopped wanting to be around him, he blamed everything but his own shitty behavior.
I don't know if that's what happened in his case, but it certainly sounds like it.