Engine Oil Leaking problems of the 2008 Toyota Prius

My car had performed perfectly for the first 100k miles. By 112k miles the oil was very low, no oil on the dip stick when I went in to have the oil change. Yet there was no low oil light or engine light to warn me. This was a complete surprise to me since that had never happened before and the usage had been at a normal rate up until then. I began looking for leaks, etc with no evidence of that. The next service it was again extremely low. I now know that I must add about a quart every 1000 miles to keep up with its demand. The dealer and other mechanics all tell me the only solution is a new engine. Some suggest a used or rebuilt one though they are still many thousands of dollars. This problem, they say, will only get worse, clogging the spark plugs and potentially having an incident of engine stalling or shutting totally down while driving. This is a safety issue that Toyota should be fixing. I paid $1500 for an extended warranty for the first 100k miles with no problems, and now, it seems, I am stuck with a true lemon! this car should be listed with the others that Toyota has acknowledged have engine defects because it has the same problem. I will never by another Toyota unless they warranty this issue. The word is getting out. They do not take care of their defect problems. So much for the very undeserved reputation of many Toyota models!.