I think you need to get to know some actual everyday Christians and stop operating off of stereotypes. Simply because one Gothic person may have atheistic thoughts and ideals does not mean that every single one must. Thats the beautiful thing about the Gothic subculture; given that it is a state of mind, you'll find as much variety from person to person as you would with any diverse group. There is no real "core" set of beliefs or ideals that one must have to be gothic. To believe so is ludicrous. The base set of Christian ideals are:

-Believe in God
-Love God
-Treat others as you want to be treated
-Repent for wrongdoings

I see nothing in the Gothic subculture that conflicts with these. Do you? You shouldn't, because there isn't anything. You seem to be going from an outside/hostile view of Christianity, which is simply not the way it is. You can't lump all Christians in with the precious few who act like morons. To do so is hateful, spiteful, and just plain wrong. People from fringe subcultures complain when they are a victim of this, yet many of them (they are, usually, "posers," for lack of a better term, anyway) do the same thing. Its no more fair no matter which direction it comes from.

Everything that you mention is an angle of the Gothic movement - - but nothing was ever started until Siouxsie Sioux and The Banshees made the transformation from Punk to Goth many decades ago. In fact, the Punk and Goth movements are closely related, moreso than the things that you mention. Certainly, those authors and thinkers are an inspiration, but that doesn't put them in with the movement in any way, shape, or form. They're just that: an inspiration. One can be inspired by any number of people, but does that necessarily mean that they share beliefs? Certainly not.

I think that you've been operting off of the wrong idea of the gothic subculture when you considered this. Its not your fault; there are a lot of misconceptions out there. But in any case, I hope this helped. If not, I may have to kill you for the waste of 15 minutes in thinking out exactly what I wanted to say...I'm never getting those 15 minutes back, you know.