The only possible thing I can think of you're referring to is his original post regarding this:
Saying it's ironic that the right leaning "drug addict" is saying unhappiness is a liberal trait.
I mean, okay, sure. Maybe that's what Keller's main focus was on (doubtful) but even if that's the case he still said Rush said Robin Williams killed himself because he was a liberal. He has even reiterated this at least twice since then.