without having any knowledge (if any of us really do) of Eldrich's relationships and that sort,
i always thought that the "you're" in the begining, ( ..."the ground is frozen through and you're driven, like the snow") was not a reference to another person, but more of a way of Eldritch explaining himself. In that context, the first seven or eight lines of the song seem to tie in alot better with the rest.
i think that it would be about his ex clair or whatever her name was, but if he wont play it on stage because its so personal, then it would seem that its more about himself... if that doesnt sound like too much s**t.
i never saw this as being another drug song.. but you cant ignore the "and the mist will wrap around us, and the crystal if you touch it" and so on.
and if all sisters songs were drugs songs, then i dont see how they would be much more than any other s**t junkie band screwing around with that kind of music.
i dont know about that 5th dimension stuff though..
just keep your nose to the grindstone they say..