This is exactly why such a complete self-deletion is worrying. I wasn't around in the neolithic days of the internet, but some people may remember that an early formative event in the WELL days was that a very well known and active contributor to the site deleted his entire posting history and then commited real life suicide. I dearly hope this has not happened and _why has simply moved on to other things...
I guess you're thinking of Tom Mandel. First, he deleted his posts after a tiff with his ex-fiance. Also, he died of lung cancer, not suicide. Full story here:
I don't remember the fellow's name, but the anecdote was related in a book about online communities written by Clifford Stoll, and definitely involved suicide, not cancer. But the anecdote he related could have been incorrect...