what is my right if my book publishing has constantly been delayed for the last 3 years when i have paid over 25 K already?

Without knowing more facts, a three year delay makes the transaction look like a scam. Don't pay another penny and get the commitment in writing. Demand to know what value you have gotten for y our $25,000 (e.g. editing, etc.) but perhaps you will need to sue for a refund.