Convincing Your Spouse
I think I'm in a fairly common marriage for preppers. The prepping is my focus, and my wife supports it, is patient with my plans and schemes, but doesn't take an active interest. She leaves it to me to worry about the bad stuff, and trusts me to take care of her and our home if it hits the fan. She buys me Christmas presents like a Nuk Alert and a fire starter, and is fine if I plan some budget money each payday for prep purchases.
I know of some preppers who have fully involved spouses. They work together to prepare their homes and families. They go to training classes together, read the same books about prepping, maybe one cans and one dehydrates, they plan the gardens together, etc... I think my wife is moving in that direction.
I know of others whose spouses have no interest, or even negative interest. They believe it is all gloom and doom or conspiracy theory. The prepper spouse can't talk about plans or problems, has to hide the extra food and supplies, or has to come up with alternative explanations for why something gets done a certain way. The spouse is a hero when the power goes out and the flashlights immediately come out, but the enthusiasm is short lived.
I think most anti-prepping spouses don't feel that way because they think their spouse is off his or her rocker. It's because they are afraid and mentally shut out the possibility of a threat to their way of life. Ignoring or denying the possibility of a disaster striking home is easier on the mind than acknowledging that some level of disaster will strike at some time, which prepping forces a person to do. It's easier to dismiss a spouse's prepping plans and gear than it is to face the prospect of using it.
What Can You Do?
I think the best approach is a gradual one. Don't say we need a generator for when the ice storm causes us to lose power for 4 days in the middle of winter. Next time the power goes out for three hours because a drunk runs into a transformer, calmly suggest that a generator would have made it more convenient. Next time your favorite brand of canned chili is on sale, pick up a couple extra cans for the pantry. When you open up one of the cans, note how much money you saved by doing the opportunity buy when it was on sale. Verbalize how eating tomorrow on today's prices can save the family a lot of money over the course of time. Instead of buying the latest and greatest M4 clone to ward of the zombie biker hoards after the global apocalypse, comment on a couple of the "Armed Citizen" articles in the NRA magazine and suggest getting a Remington 870 with a shorter barrel for home defense and a longer barrel for hunting or skeet shooting.
Don't drag the spouse off to Arizona for Cody Lundin's desert survival course. Have the family all go through the FEMA on-line course, "Are You Ready?" Rather than coming home from the store with enough canning supplies to put up the entire farmer's market, get a jar or two of green beans and strawberry jelly from a friend at work, then talk about how tasty it is and more nutritious than Del Monte or Smuckers.
If your negative spouse is rational, and you approach the topic rationally yourself, most can probably be brought around to at least acceptance. A spouse who is accepting or tolerating can often be brought around to being a fully involved partner by you being steady, sensible, and non-pressuring.