I sure know how you feel about "wasting" the batting & backing on a quilt you really don't like. Where is the law written that you HAVE to finish it. Why not put it into a thrift store bag & let another quilter discover it & may love it while you don't.
It's hard to spend so much time on it when your heart isn't in it. Nobody will put you behind bars for it & somebody else may finish it.
We sometimes forget that we're in charge of that top.