Incredibly, it took me a while to figure out what in the heck was wrong here. I knew something was wrong.

The first thing I noticed was that there was no fire in the fireplace. Since I'd seen Cain wander over there a few times, I was gonna give him some crap about letting it die, but where is Cain? For that matter, where is Tyrael? And hey, where's my stash?!

The problem was resolved by taking the waypoint out and back again.