SadGirl is describing me as well. Having bipolar I am prone to bouts of depression. I've been hospitalised twice - both times during what should have been happy periods in my life. Having depression may have nothing to do with how well or well not my life is going.

I want to point out too that even those who appear to have it all may really be struggling. Maybe what they have is tenuous and they worry about losing it all. Maybe they have a particularly poor view of their self-worth, maybe they are desperately worried about failure or not living up to expectations.

Your question is timed to coincide with several high profile suicides. I think these people were feeling all that I have mentioned. First of all, they were incredibly talented artists which fits the bill for having mental illnesses. Second of all, they must have been under considerable pressure to be creatively productive. I imagine then the fear of failure and questioning of their self worth contributed to a pre-existing mental health illness.