I don’t understand long term stress. Surely if the job is causing you so much stress that you can’t even think about working there for 6 months than surely you resign and find another job that won’t cause the same stress!
(!) It's not always that easy to just find another job that won't cause the same stress! If it were, more people would be doing it. Jobs, especially relatively non-stressful ones, don't grow on trees.
(2) It may not be that your job is causing the stress, but that your existing stress is making you unable to do the job properly or perhaps at all. Just like you may not be able to do your job if you've broken your leg; but that doesn't usually mean that you broke your leg at work.
One problem is that in this sort of context, any mental health problem tends to be labelled as 'stress', partly because, understandably, people and their employers tend to avoid giving lots of public detail about their mental health problems. People with bipolar disorder or severe depression may be temporarily unable to cope with work-related stresses, but this doesn't mean that their illness is just about stress.
There are piss-takers around, but in my experience they tend to be people who find excuses for lots of short-term absences, and always suddenly have the flu on Mondays and Fridays, rather than those on longer-term sick leave, who must undergo much more scrutiny and health checks. I don't think there's much one can do even about the former, especially right at the moment: I'd rather that someone left me to take up the slack for their absence, than came in sick and gave me Covid! But it shouldn't be taken out on the longer-term sick.