Welcome to the group! This is a good group to give you that kick you need to get you off of the Sub!
You had the right idea... taper down and keep going until your down to pieces and jump off. The rule of thurab that I learned here was taper down 10% at a time, allow your body to get used to that level (a few days) and taper down again. Cut your pills in pieces at the end when you're down to the lower amounts.
If you went from 5 mg/day to 5 mg/week w/o withdrawals, try that again. Once you feel withdrawals start, either bump up to the previous dose for a few more days and then taper back down again. If the withdrawals are minor, see if you can stay on the new dose and push thru them. Stay on that level a little longer and repeat the process. When you're down low enough and you feel like you might be able to handle it, stop, work through the withdrawals and poof! You're new drug-free life begins. Then you enter the next stage of the cravings and keeping yourself off of the drugs for the rest of your life.
I was too durab to follow the advise from people on this board and I was dropping 50% at a time and dropping another 50% a few days later. I was on Oxycodone. I suffered severe withdrawals. I finally went cold turkey and worked through it with a little help of Valium for 4-5 days. In on Day 17 right now. Search for "I am Oxy" which is something I wrote that might make some sense of out it all.
Glad to see you are thinking about starting the process and I really hope you will follow through with it. You'll get support here from us.