Often employers contract out Occy Health - at my last job, it was done by the local hospital, and now it's "in house" but the doctor is an NHS one.  I had to go about eighteen months ago (hysterical blindness caused by overwork) and he was brilliant - I was terrified, as he has a really fearsome rep, but he couldn't have been nicer: and he wrote a very fierce letter to our HR (who are bloomin' useless) - the good news is, once Occy Health say something has to be done, HR have to jump: so hopefully. they'll sort your ghastly managers out for you - Good Luck!