Stories like this make me sad. Methadone is a much stronger narcotic than either Darvocet or Vicodin. It's only advantage in the clinical sense is that it's so very long lasting that you don't need to take doses more than once a day, but when it comes to withdrawals, any junky will tell you that methadone withdrawals make heroin withdrawals seem like a stroll in the park.
Nevertheless, if you can slowly wean yourself down, you can get clean. It won't be fun during the process but once you're clean you'll feel great, I mean "burst of energy" great, a new zest for life, food will taste better, sex will be better, the whole ball of wax.
I hate to constantly be evangelizing suboxone but let me just say it worked for me, and I had a very bad habit--injecting heroin or dilaudid many times a day. If it can tackle a habit like mine was, I find it hard to believe that anybody has a habit that it can't help with. It's worth at least mentioning to your doctor.