I dont mean to sound arrogant but I can tell you exactly what she wants to hear....
"Babe, dont sweat it. we're going to be fine. I got you."
The cult may be fanning the flames but in the end we all have moments of insecurity. Our wifes want us to be their rocks in times of trouble, same way we want them to tell us they still love us and believe in us when we screw up or feel inadequate.
Let her know its all good, come what may. Set the cult crap aside on this one unless she brings up the specifics in which case you can just leave it as 'we will deal with it when we get there. Until then were moving forward' (she dosent need to know forward is away from the cult)