So the difference doesn't really matter. You have a bad boss; take care of yourself first and don't let them push you around.
So? That's the boss's problem to deal with. You owe the company absolutely nothing beyond your contracted hours in exchange for your contracted salary.
I say this as an employer.
If your boss happens to be a cog in a broken machine, treating them like it's their fault isn't fair to them or you.
Of course, you can always quit (and usually should). But failing to determine root cause and mis-blaming your boss is about as useful as screaming at the gate attendant when your flight gets a weather delay.
And someone who by choice decides to be (or remains) a cog in the broken machine, specifically at the point where it requires being nasty to someone, is fully responsible for that action and its consequences.
Because sometimes the situation is bad for your boss too, the company is in financial straits, miscommunication, {insert other extenuating circumstances}.
... but sometimes your boss really is just an asshole, liar, alcoholic, and/or a sociopath.
Never assume the later off the bat, but never completely discount the possibility either. Because it'll probably happen at least once in an average career.