I was only diagnosed bipolar less than a year ago, but have struggled with it all my adult life. Work-wise, I do well in job for maybe 18 months and then start to get frustrated and over-sensitive to my colleagues, leading to more and more sick days and more and more erratic behaviour. Luckily, for the past 6 years I've worked in a large company where it's possible to transfer across to new teams quite easily, so I'm now in my 4th role in this same company. I still find it hard day to day, although my diagnosis (of which my HR department is aware) and subsequent med adjustments have helped me more than I can say. Like most people, sick or not, I need to work and even though I hate the idea that my boss might be looking at wondering 'Is she gonna flip...' the fact that the company is aware of my condition is a comfort.

Having said that - and as other posters have said above - everyone suffers in different ways and some people will never be comfortable in the working environment.