@Off the Wheel, My condolences. It is a very difficult thing to go through; I hope you can be kind to yourself, whatever that means to you.
I think I've failed at this challenge. I tried, but the problem is, if I don't buy any clothes for 6-12 months, I start to feel frumpy. I know this is exactly how the materialist-capitalist system wants me to feel. I'm a consumer sucka, but there it is.
I try to avoid anything too trendy, and I buy clothes and shoes in a limited color palette (black, white, gray, blue), but I still feel the need to refresh my wardrobe with 2-4 bottoms, 4-6 tops, and perhaps 1-4 pairs of shoes each year. I find that maybe only 50-70% of what I buy ends up in regular rotation: some things that initially look good end up being not quite as forgiving as I thought, or too tight and uncomfortable around my neck, or too sheer, etc. In my post-pregnancy middle age, the range of clothes I can confidently wear is much narrower than when I was younger. Some of what I buy is to replace what's become misshapen, worn out, or pilled, but it's definitely more than what's strictly necessary.
I think I've had similar feelings about my wardrobe and shopping habits. I'm pretty sure I haven't fully resolved it, but there are a few things I think have helped...
-keeping track of the types of things I buy and wear a lot, vs the types of things that I like but don't end up getting a lot of use. For me this tends to be most related to fabric (I tend toward soft), too-tight or too-short cut, or dressier than my usual style. I've also discovered I really can't get away with non-petite sizing on many tops (arm holes show bra or button downs ride up and sit funny). I've tried to stop buying things that I don't *love* when trying them on, the things I just "think I can pull off".
-pushing myself to wear what I have, both pushing my style from comfort zone to aspirational zone, and not "saving" my nicer/favorite clothes until they don't fit, are out of style, etc.
-gentler care regime (fewer washes, hang drying some things)
-paying more attention to materials and how they age. I've noticed my cotton sweaters tend to fade & stretch and acrylic ones get scratchy. When I replaced my cardigans I found some light merino wool ones...I like how the knit and fibers have held up over last winter, but they did seem to develop small holes easily so I might try a different brand once they're beyond repair.
I have also made peace with the fact that certain high-wear items will just wear quickly. I seem to burn through my dark-wash skinny jeans and flat everyday sneakers...because I wear them several times a week!