What Price Privacy?

A few months ago, my officemate---Let's call him "Bob"---was out for about four weeks* for "treatment of a medical condition." Now, those of you who've met Bob know he's a very laconic individual; most of the time, he works away quietly on his computer, and I hardly know he's there. Thus, you won't be surprised to learn that "treatment of a medical condition" was the only explanation---or even acknowledgment---of his absence I received. Now Bob's been gone for an additional four weeks,* with no indication of when he will return. I've certainly enjoyed having my own office---though it's not that different from sharing one with him**---but I don't think I want to have it at the cost of some serious illness to a nice, if shy, engineer.

* He was supposed to be out for three weeks.
** See previous comment on Bob's taciturnity.