I did the same thing with a thrift store angora sweater. It is just SO delicate and breaks so easily that unraveling it proves to be very challenging, if not impossible. I know I haven't had luck with it - I chucked the whole thing in the garbage
. For recycling sweaters, I tend to stick with strong fibers (wool, cotton, even acrylic blends) and worsted to bulky yarns. Anything else isn't really worth the pain for me!!!!