I'm a *little* angry no one has responded to this. Where's the supportive community!
Let me ask you a couple questions: how in shape is your wife? More in shape than you? Is she satisfied with her health and fitness? There could be some superiority complex, some denial, a sprinkle of ignorance, all these things. If anything, imagine it like this: she probably views you have the mentality of a trendy fruitarian and she the knowledge and authority of orthodox paleo you might see roaming this forum. Get it? To her, she's the sensible one and we're the wacky ones, SO wacky it's probably unsustainable in her eyes.
Eventually this will go away.
Most people won't buy into a diet unless they see someone maintaining the lifestyle and particularly thriving on it. I'm sure you've thought about it pretty long though, so don't let me lecture you about it! Just know that I believe your wife WILL come around to accepting your lifestyle. As she keeps seeing you leaner and fitter and healthier and happier, she'll totally buy in. Like my aunt in Oregon: she's on this whole juicing kick and now my mom has bought a juicer and is joining her. I'm not a huge fan of juicing but, my mom saw my aunt consistently stick to juicing for the past year or so, hear the results (she apparently feels better blah blah blah), and it's pretty much convinced her and my OTHER aunt. Results speak.
Many health gurus, raw foodist and carnivore alike, who would consider the "everything in moderation" people as, well, lazy and moronic...simply by virtue of placing this well-intentioned philsophy as a comforting blanket over their food choices as opposed to actually reading and eating smart. I wouldn't consider your wife lazy or stupid. Hell, even most people here believe in 80/20! How's THAT for moderation! It's probably the relative moderation though that's getting her. Having a beer once a week and 1 square of dark chocolate a night is moderation for most here. I would guess to her that would be "insane" and "obsessive." However, that's just me putting words in her mouth. I don't know the whole situation, but that's how others react when I tell them!
My best advice, if you'd like to hear it, is to really let it lie. Don't bring it up. I've gotten a couple people I really care about to try this diet. And our conversation went like this: "I've been trying this interesting diet for a while now and I really like it. Would you like to try it with me?"
Simple as that. No prefacing lectures, just asking them to join me. That's had the highest success rate of buy-ins. For some reason no one wants a lecture on diet, for reasons unknown; but, people DO like trying new "fads" and bonding with their friends/family in the process. Many people consider it fun. And then I hear comments like "Wow, I haven't been having to go to the gym as much to stay in shape and I never feel bloated," and "Wow honey! I'm now a size 6! I'm gonna look so hot at the Christmas Party! Can I borrow your new dress?"
The last one was my mom and she looked pretty good in MY dress. Bah!!
Lastly, the best way I have dealt with the paleo/primal thing is sincerely never talking about it. And with my family I'll cook hash browns and bacon for breakfast, chicken in a curry sauce for dinner...just good food my family doesn't even realize is pretty primal. It's funny how moms freak out when they want to start feeding their kids primal. I bet 80% of the diet is primal; unless you're a cereal/pasta/KFC-bowls/Panda Express kinda family. Just make good food and subtract bread. She won't even know what hit her!
Hope this all helps. I'm no expert for advice of course. Please keep posting!