I think you would actually find, were you to really listen to them, that most atheists do not hold their own viewpoints as absolutes, and would be more than willing to listen to any tangible, measurable evidence of god's existence. Heck, there are probably quite a few who would love to be proven wrong--the notions of a loving creator and blissful afterlife are certainly tempting--but lacking this evidence, and finding that a bit of critical thinking seems to blow apart most religious stories at their poorly-stitched seams, they have come to an inescapable conclusion that even if there were to prove to be some sort of supreme being out there (which, all atheists not being equal, quite a good percentage of them will concede that it is, however unlikely, still possible), this being is not one which is accurately described by any single faith out there.
Old Church Guy is well-liked around here despite his religious beliefs because he will also concede that there is a possibility that he is wrong in his beliefs, but since they resonate for him, and he finds a personal comfort in them, he is not willing to jettison them on the off chance that they might prove false. He has never, to my knowledge, made any claim that someone not sharing his particular viewpoints is bound for hell.
As far as I know, he also doesn't seem to share your view regarding demons and their ubiquitous (according to you) meddling in all lives and religions, seeking constantly to lead us all astray.
Frankly, I think that this part of your theology is what rankles the most, since you are so absolutely convinced of the presence of these demons, and so adamant that only you and a seemingly very limited number of other people out there have managed to interpret the Bible correctly because of their interference, yet at the same time refuse to even consider that there is every chance that you might have, by the same definition, been led astray in some of your own interpretations of a book in which it is notoriously easy to find multiple interpretations. And that, again by the same definition, you would never know about it because they would have been successful in misguiding you.
You can't logically hold that world view and still be immune from it.