If you really look at it, it looks like there is a theme. I think the fab spans three decades, 60's - 80's. You can see it if you look at each selection of different fabrics. I wonder if it was a family quilt, maybe clothing made for or by that family, remnants sewn into a quilt, perhaps as a gift.
What you could do if you want to rescue it is remove the backing, iron it as flat as possible, then fuse a light interfacing to it. You wouldn't have to worry about the fraying pieces and if you attempt to take it apart you may lose more than you think. Then just back it with a fleece and tie it, or whatever your preference is.