I am way sympathetic with your experience and have been decrying the same things for years now. I am probably 20 years your senior, since I have great grans, but let me assure you there are stores out there who have quality cloth. I have no idea where they get their supply, but it is there in a place or two. I found one shop in a remote district of SC one year and you can imagine they charged well for everything they stocked. I think I paid about $25 per yard for what I bought. Colors were bright and clear and designs were outstanding.
At the same time I saw the quality of cloth changing, I also saw shops going to crafty junk rather than true sewing quality. I wanted Swiss batiste for smocking and dotted Swiss, etc, but all that died when the craft stores took over. Quality was not the order of the day after the good cloth went out.
Keep searching! Ask neighbors and friends who also sew and one day you will find that special shop.