Maybe Robin Williams' suicide wasn't an act of depression, perhaps it was a sane, rational, even wise decision. A choice. We don't know because he didn't leave a message. But that's okay, most people who die don't, and a lot more people end their own lives than we recognize.
Sometimes life is over, or it's changing so radically, that the story-teller of our life, ourself, decides the ending shouldn't come after years of suffering, rather the end should come when the great part of life is over. And Robin Williams certainly had a great life, even if he did a lot of drugs, and was often unhappy. I don't think there's any doubt that he delighted in sharing his brilliance, and when he was on, he really did shine bright.
He decided early-on to lead a creative life. And he always did the best he could with what he had. I love the pictures of him as a mime in Central Park in the early 70s. I spent a lot of time there myself then, it's possible that I saw him. It's so perfect that he, a student, at the time never a guest on The Tonight Show, still found a way to be Robin Williams. What an inspiration. Don't wait to be creative. Do it now.
He wasn't always on as a performer, but he stretched, tried all kinds of roles. He wasn't limited by his money. There are countless stories of him with other much less famous, rich, or accomplished people. I think that's really important. For a lot of people creativity dies when they achieve success. But truly creative people just are creative with the extra tools and toys successful people get to play with. Williams was the latter kind of successful person.
He had a great life. It was over. (Said in hindsight.)
Sometimes, for some people, in some circumstances, they get to say when it's over, and have the courage to act on it.
That's another theory about his death. I don't know if it's correct, but I haven't seen anyone else put it out there, so I wanted to.