Alrighty, folks. I'm playing on a PC, so when Delfine refused to speak to me after I killed Sahlokniir during A Blade In The Dark, I did the natural thing. I reloaded from a recent save, killed Sahlokniir again, and tried to speak to her again. It turns out this is a documented bug http://www.uesp.net/wiki/Skyrim:A_Blade_in_the_Dark, but although others have had the same problem, no solution is suggested there. After three tries with variations in the point I reloaded from, plus fast-traveling away and back again, I gave up on this method and looked for a console commands solution, eventually settling for "setstage MQ106 200". This appeared to work, as the quest was completed. I went on my merry way thinking I'd solved the problem. Hooray!

But my celebration was too early. It wasn't long after when I realized that Delfine hadn't started the following quest, Diplomatic Immunity. Once again I tried to fix it various ways (talked to Delfine again, setstage command, resetquest command) but no matter what I do, I can't get that next quest to show up in my quest log.

Now, I did consider reloading from a still earlier save, and in the end this may be what I have to do. However, this requires (1) retreading several hours of content and (2) maybe still running into the same bug again anyways. So, I'd really appreciate it if you folks in the audience could point me towards how to fix @#$%^&! Delfine and her @#$%^&! quest.

Thanks in advance.