If you do figure it out, let ME know, as I've not only never figured it out myself, but I've also never seen anyone's recommended "system" work (at least for more than a brief period of time).
People seem to just be libido-mismatched sometimes, and the only thing that seems to work is "fear of loss," but how many times can you play that card?
You're either willing to -- or NOT willing to -- live in a sexless, affectionless marriage. Once the low-drive spouse knows (by your actions, not your words) that you ARE pretty much willing to, I don't see them ever changing.