When a person gets to be my age, she has long since realized that certain doors have closed. Unlike those teenage years when everything not only seems but in fact is still possible, at least on paper, I some time back began choosing doors that caused other doors to close for good.

When a person gets to be my age, she has long since realized that certain doors have closed. Unlike those teenage years when everything not only seems but in fact is still possible, at least on paper, I some time back began choosing doors that caused other doors to close for good.

I never expected to go through most of them anyway. Although I was fond of talking about working for my passage on a tramp steamer, I was no more likely to climb aboard one as I was to take up opera singing. I wouldn't have known where to find a tramp steamer, for one thing, or even what a tramp steamer was.

My husband - though he wasn't my husband then - and I also discussed going to Alaska to live off the land, though we never so much as crossed the Canadian border until we were married with two children who wanted to see Niagara Falls. (Also, I realize that our visit to Niagara Falls put us even farther from Alaska than we usually were.)

My point is, I feel no melancholy when I consider all those untaken roads. Opportunities continue as long as life itself does, and I now know better than to flirt with the ones that are as suitable for me as overalls are for fish.

Life is simpler now. When someone says, "Want to join a cooking club?" I say "No." The day was when I'd have clung to the fantasy that I would ever want to make, say, pan-seared halibut cheeks, but that day is gone.

I've also gladly accepted the knowledge that I will never play bridge, study Morris dancing or appreciate the differences between rotary and piston engines.

And why am I so happy to relinquish these possibly fascinating pursuits? Because I've learned that what I consider vital to my personal satisfaction takes up all of my free time and some of my other time as well.

I realized this not long ago while listening to my daughters and their husbands discuss wine. All of them understand far more about wine than I do; my older daughter and her husband in particular have studied wine the way some people study logarithms, with far more pleasant side effects, and now they're extremely knowledgeable about what to drink, and why, and when, whereas my husband and I tend to choose wine with a sort of wild optimism that falls just short of closing our eyes and pointing.

On the other hand, I appreciate other things. Thread counts, for instance. Until I was well past voting age, I scarcely knew thread counts existed, let alone their significance, and now I wouldn't dream of bed sheet shopping without making the thread count my number one priority.

Those of you who are into French perfumes or Manolo Blahniks may not know what I mean by thread counts, so I'll explain: Bed sheets with a thread count of, for example 500 have 500 separate threads per a one-inch square of fabric: 250 in one direction (the warp) and 250 in the other direction (the weft).

For a long time I considered 200 a high thread count. It is a high thread count, considering that I'm a person who once selected bed sheets purely by price and, sometimes, color. My sheets then were as smooth and soft as frozen burlap; I didn't realize they could be any other way.

Then I stumbled across higher quality sheets -- sheets with a 350-thread count, maybe, or 400 -- and light began to dawn.

These sheets were weightless. They were creamy, almost velvety to the touch. I felt like Columbus, sighting land, like a Wright brother as the ground fell away.

And if 400 threads could do that, what about 500? I began lurking around linen departments, pawing through the merchandise with wild surmise.

Discovering the incomparable luxury of 600 threads was the result of a miscalculation regarding the size of a relative's mattress while buying Christmas presents -- Oh! They're just heavenly! -- but now I'm caught up in the possibilities. Seven hundred- thread sheets are out there. Nine-hundred-thread sheets are out there too. Considering that each upward ratchet of 30 or so threads adds another $50 to the price, my innocent habit could lead us to ruin.

But we'd go there comfortably.

Margo Bartlett is a ThisWeek staff writer. E-mail mbartlett@thisweeknews.com

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