Two of these I did previously and one this morning. I thought people might be interested in the previous ones and might even share their own. (Or maybe others have shared similar projects before I joined.)
The first one is a blouse that belonged to my dear friend Maren.
When Maren died, I inherited the blouse. It was too big for me but I devised a way to make it into a skirt. All I had to do was sew the sleeves shut to make them into pockets. The neckline became the waistband. The back of the shirt became the front of the skirt. The buttons make the waist adjustable (see photos).
The second makeover was an A-line skirt I bought about 25 years ago. I outgrew it 
so I made it into a top.
Back detail
Today’s makeover was a knit top that I bought at the thrift store a while ago. It was too big but I liked the fabric.
This morning I wondered whether it might work as a skirt. Unbelievably, it worked perfectly–the waist was perfect and the hem straight (even though it looks a little shorter in front in the photo). All I had to do was whipstitch the sleeves closed to make pockets.
So, there may be options for the thing that’s not working now but that you’re reluctant to part with.