Apologies for beating a dead horse but would any of these options grammatically make sense or work for 'don't let the 'jerks' grind you down' as bastard wasn't a thing apparently? I know nothis is an option but id like something that's an insult in classical latin?
Non te irrumatores terere
Ne te irrumatores conterere
Noli sinere irrumatores te conterere
Noli irrumatores permittere te terere