Hi - I'm so sorry to hear about the time you've been having. I too have been through everything with severe over pronation and instability. Orthotics didn't help me either. In fact my problem got worse after I started using them and I couldn't live without them either. I finally had triple arthrodesis on both feet and achilles tendon lengthening. This is a HUGE - MAJOR reconstructive surgery but was really my only option. I am so glad I did it though. It was very difficult and a long recovery. Learning how to walk again was difficult and painful but so much worth it. My second one is coming along and the first one is so close to normal it still amazes me. There is something else that can be used in SOME people. It is called the MBA implant but generally isn't used as much with success in adults with more severe deformities. It is a less complicated surgery and involves putting a small screw in the Subtalar joint to create an arch and is reversible if unsuccessful. Careful evaluation before surgery is important though because not everyone is a good candidate. I wasn't and am glad I didn't have it done when it was first suggested. It saved me a lot of pain, money and heartache. I'm very happy with what I had done although I would have loved the less complicated implant surgery !
Let me know if there's anything else I can help you with.