The worst part of it is that I felt totally fuzzy in my head. Like I couldn't argue my point well. I began to actually feel like "what is wrong with me?"
First off, cults work very hard to instill this sort of self-doubt into their victims, especially those that are having doubts about the cult. Keep reading, researching and soul-searching until you have complete self-assurance that you're of right mind, pure motivation and are certain that it is not "the truth." Do whatever it takes to get there. Just know that you're not alone, and that the way you feel right now has been ingrained into you for the purposes of control.
If your marriage has any chance of success you're going to have to communicate well. Big surprise there. Talk to your wife. When she attacks your motives (perhaps without even realizing it, i.e. "why do you go if it's just to criticize?") point out what she's said, how you've interpreted it and how that makes you feel. If you're going to support her, you need to let her know that and make sure that this is what she wants. You're not a martyr for making sacrifices for someone if they don't want what you're giving them, so make sure it's what she wants before you make the sacrifice.
With any luck you'll be able to get your wife to trust you, trust that you're motivated by a love of truth (real truth) and a concern for your (and her) well-being. If you can get to that point, you've made a huge stride. I never was able to get my wife to trust anything I said, though, as she would fall back on insisting that my thinking was being manipulated by the devil and I couldn't be honest about my motivations even if I wanted to, etc. etc. That's what eventually lead to the end of my marriage. I hope that your wife will be more reasonable (and less superstitious) than mine was and that you two will be able to (re)establish trust and communication to get through this. If you're able to do that, then you've got a decent chance of waking her up eventually, too.