I think I can truthfully say this is the biggest topic this forum's ever had, currently with 56 posts (including this one). Kudos to Milk Man for starting such a great discussion!
Anyways, I'm convinced that The Deceiver and Ravanna/Shiver were "bedfellows" in a literal sense at some point, before she was killed at Madrigal. Some evidence:
1) In "Shiver", the deceiver says "The path to retribution does make for strange bedfellows". Here he is clearly referring to his alliance with Alric, and using "bedfellows" to mean "ally" or "comrade". Right after that he says "Would you not agree, Ravanna?". This could be referring to her alliance with soulblighter. This doesn't seem right for a couple reasons. First, when he says "Would you not agree, Ravanna", he says it in a conspiratual tone. Ravanna's alliance with Soulblighter is completely open, so this doesn't make much sense. Second, she gets angry and attacks him right after he says it. Again, if he was referring to the Shiver/Soulblighter alliance, there would be no reason for her to get mad.
"Would you not agree, Ravanna?" could instead be an allusion (not illusion) to the romance I believe they had. The Deceiver seems like the kind of guy who would enjoy using puns, since he seems to be a well-learned man, and he is (IMHO) using "bedfellows" in both ways. This would explain both why he said it in a conspiratual tone and why Ravanna got mad at him.
2) Later, The Deciever says "The years have not been kind, have they Ravanna?" Aside from being an insult, notice how he says "fair Ravanna" instead of just "Ravanna". This suggests that he knew her when she was "fair", and sounds like something a former lover would say.
3) This is going out on a limb, and it's just an idea, but Myrdred and Ravanna's relatively simultaneous deaths might be kind of a Romeo/Juliet kind of thing. Granted, Ravanna and Myrdred are hardly lovers when they die, but it fits the Bungie pattern of making references to a bunch of other stories in all their games(The Black Company, Ringworld, Tolkein, etc.) whether it was intentional or not.
