Excellent. Yes. I'm sure there's lots of common ground to be uncovered here. However, I do disagree with your insisting that the symbolic structure is fixed. For instance, look at the Lacanian formulation of the "authentic experience of Love" as you stated. He calls it, "The Encounter with the Real" and furthermore, he says that it is inherently traumatic. Now this is a completely different style of going about this. It's demonic, but it aims at the same thing. We can, and we should invent new concepts, that's what philosophy is all about, according to Deleuze! I would also add that Foucault would say that there are multiple "authenticities" not just one (as that would take us back into the realm of universals). But like I said, it's very possible that Foucault is playing a trick on us all, like Lacan, only pretending to deny the unity, so that we discover it on our own.