When you feel lonely? I may be overgeneralizing my own introspection here, but at least feel sliding towards the reply-guy behavior when I'm actually lonely, in a particular way, and try to get a hold of a conversation, but am also too tired to do it well...

Ah, that’s an interesting thought. I can well imagine that that’s a driver of some of the behaviour. Some is just good old fashion social ineptitude disguised as confidence too though, I think.