It means you're being/doing/saying something unpleasant and you need to go away and get lost.
A person who is upset at someone else's actions tells them to "
Screw yourself". They could also say Fuck yourself instead but Screw is
the cleaner version.
Q: How does "Screw yourself" or it's equivalent "Fuck yourself/Piss off" mean 'get lost'?
A: 'Screw yourself' implies before this bad transaction between 2 parties. The analogy in this sexual metaphor is that it WAS a mutual and pleasant affair between the 2 parties BUT now the offending party can do it all alone (Masturbate) because they're no longer welcome in each others company.
Ergo,
screw yourself cuz I ain't fuckin'
witchu no more
Husband comes home from work to hear wife yelling and complaining again at him as soon as he walked through the door but their children are present, so he responds: "You know what I'm tired of you telling me what's wrong
every single time I come home from work.
Go screw yourself, I'm out!"
