The last time I had a really good night’s sleep was Nov. 4, 2009. It was terrific, although I may have been dreaming.

Since then, not so good. I sometimes go to bed too early, I sometimes get up too soon, I toss, I turn, I worry about the National Security Council while I should be snoring.

I blame it all on the mattress, mainly because my wife said I absolutely can’t blame it on her. And, in fact, it actually might be the mattress’ fault.

We’ve had this mattress since the early part of the century, and I’m not sure which century. It has a lot of miles on it, many lumps, several valleys, the occasional gorge and it argues with the pillows on a regular basis. It has been declared a UNESCO World Heritage Site.

When you turn over on this mattress, it creaks. When you don’t turn over, it creaks. When you look at it or talk to it, it creaks. Sometimes it whines, occasionally it comments online on news articles, generally using a fake Facebook account.

So we’ve decided it’s time to get a new mattress. To that end, we have been doing our research.

What we want, of course, is something simple — white, rectangular, feels good, no lumps, no online comments. But mattresses, it turns out, come in an overwhelming number of varieties, including pistachio.

You can get memory foam or latex foam, adjustable air or inner spring, pillow top or super pillow top, low calorie or high fructose. There are posturepedic and tempur-pedic, naturepedic, orthopedic, encyclopedic.

Really, we just want a plain pedic, as long as it doesn’t have lumps.

So we went out to the mattress store to narrow the choice down to just a couple of hundred possibilities.

But here’s the real problem with trying to check out and ultimately buy a mattress: it’s not like going to the supermarket and checking out a honeydew melon. You can’t just squeeze it or smell it or roll it down the supermarket aisle toward the lettuces.

The only way to decide on whether to buy a mattress is to make believe you’re sleeping on it.

You have to do this with your shoes on, while wearing your winter coat, in the middle of a brightly lit showroom, with lots of people around, music playing, with a sales person asking if he could get you a cup of coffee and with other customers making fun of your Hello Kitty jammies.

Nevertheless, we did it. We lay down on mattress after mattress. I liked the extra firm ones. My wife liked the extra soft ones. I preferred the Euro-Flex-Supreme. Her favorite was the Plush-Hybrid-Cushion-Firm.

We decided to buy a honeydew melon instead.