I bought a set of sheets from a brand called Magnolia Organics which one review described as being "like sleeping in khakis" because the material is so heavy. Perfect! They've held up well so far, but I've only had them for less than a year. My other set is LL Bean, and they are holding up well so far, too, but feeling a little thin.
I've noticed with clothing that there's a huge range of quality for fabric that feels the same and has the same weight. For example I've had some jeans (Gap, Levi) wear out after a year or less of daily wear. But my current pair (Lucky) has held up longer, maybe approaching 2 years. I bought two more of those when they had my size on sale, so I'm good on jeans for probably the next 5 years. Unfortunately it seems to be hard or impossible to predict quality ahead of time, and by the time something has stood the test of time it's probably too late to but more of the same.
Perhaps my longest lasting textile is a set of towels purchased around 15 years ago. They used to be cream colored, but now they are pure white. I use them daily, but now (only recently) they are starting to look worse for wear. The edging is coming off, one has a tiny hole, and the hand towels are permanently dingy. But I might as well use them until they totally fall apart.
Washing and drying puts a lot of wear on fabrics. I've noticed tiny holes in some shirts (and my ancient towels) as a result of the agitator in my top load washing machine. If you can upgrade to a front loader and line dry everything, your stuff will last longer.