I know the coffee enema sounds weird, but it is the gentlest, safest procedure you can imagine. Even cancer patients on the brink of death do the juices and coffee enemas (both the Gerson program and the Kelley/Gonzalez program) safely, and uniformly report a decrease in pain, improved sense of well-being, calmness, and better sleep. And more often than you might think, they move away from that brink and back to health.
You can do just the juices, but keep in mind that you'll be washing lots of toxins into the liver and then doing nothing to clean the liver. So you would need to go slowly -- perhaps no more than 2 cups of fresh-squeezed vegetable juice daily. You're probably pretty toxic, so more than that might not be a good idea.
I'm not sure what effect losing weight would have.