Well, you could quit a specific resignation letter stating that this is due to "health reasons"
I mean, I'm not sure what the specific unemployment laws are over there however that is a pretty standard provision.
You usually have to get someone to certify it though. Regular doctors tend to be conservative and therefore are less apt to make a determination of this kind. However, mental health professionals usually tend to like to help. Plus you could get disability.

I'm not advocating that but it has been know to work...