The day I watched helplessly as My Lovely Wife swelled up like a balloon after eating a crab — her breathing labored, her itchy skin breaking out in angry red blotches — was one of the saddest in my life. I knew immediately there wouldn’t be very many crabs in my future.

And so there haven’t been. When a loved one is allergic to something, it hardly seems fair to chow down on it in front of her.

Ruth had always loved crabs and was truly irritated that after 35 years of eating them her body had suddenly decided enough was enough. Allergies are funny that way. I’ve somehow ended up allergic to raw apples, which are pretty much the best kind of apples, don’t you think? About 10 years ago, I noticed that after a few bites of a nice, firm red delicious apple, my mouth would tingle and my throat would start to contract. It seemed best to avoid them after that.

I now dream of apples the way men crawling through the desert dream of water. Tell me, are apples as I remember them: the skin firm at first, before yielding to the pressure of your teeth; the flesh juicy; the experience as much an auditory one — crunch, crunch — as a gustatory one?

But we were talking about crabs. The blue crab is a staple around here, or used to be. For crab lovers, it can be hard to read stories about the Chesapeake Bay: the dead zones, the dismal annual report cards (C- last time around), the dying life of the skipjack-piloting watermen (although, actually, they’ve been dying for as long as I can remember, so maybe the news of their demise was premature).

I have crabs on the brain after speaking with Bill Wade. Bill lives in the District, where he runs a database publishing company. He and his wife, Susan Elnicki Wade, like to spend as much time as they can near the water. Last year the couple was looking for a project to do together. The result is “Crab Decks & Tiki Bars of the Chesapeake Bay,” their self-published guide to those unique attractions.

“If you go to the bay, you end up at one of those places, whether you’re a boater or just visiting for the day,” Bill said.

The couple had one firm rule: To be included, an establishment had to be on the water. “It’s not really the bay experience unless you’re at the water’s edge,” Bill said. “Why drive an hour-and-a- half to eat three blocks off the water?”

In the end, a whopping 158 places made the cut, from such popular restaurants as the always crowded Cantler’s in Annapolis to the Drift Inn, off the beaten path in St. Mary’s County. The owners say it’s the oldest crab house in Southern Maryland.

Although the crab deck — a place to spread out brown paper, crack crabs and suck Old Bay off your fingertips — has been around forever, Bill says the tiki bar is a more recent phenomenon. “Tiki started creeping in within the last 20 years,” he said. “Why? I don’t know. I think when people think of ‘tiki’ they think of ‘party.’ ”

Bar owners throw up some thatched huts and bamboo, order some tiki head glasses and — somewhat incongruously — crank up the reggae. (The Caribbean is nowhere near Polynesia.)

“A lot of them go down to Florida every year and bring back live palm trees, knowing they’ll die in the winter,” Bill said. “They don’t care.”

Researching the book required the Wades to head out nearly every weekend, something that did not always sit well with their kids, now 11 and 14. Bill and Susan once asked them if they wanted to go to the Anne Arundel County Fair. “They said: ‘Okay, we’ll go. Wait a minute. You’re not taking us to a crab deck are you?’ ” said Bill. “We said, ‘No, we’re not going to any crab deck.’ Of course, we took them to a crab deck.”

Why are crab decks and tiki bars so popular? “We Washingtonians need a change of pace every so often,” Bill said. “In 45 minutes, you can get to one of these places and all of a sudden you get to sit back and relax. It’s a whole different feel. It’s no longer the hustle and bustle of D.C.”

You can find info on the book at crabdecksandtikibars.com. Or go at 1 p.m. Saturday to the Broad Branch Market on Broad Branch Road NW, where Bill and Susan will be signing copies of the book.