First of all, I have had PF since (initially) early 1998, with a full-blown case since spring 1998. At my worst -- which was as bad as anyone here -- I was clinically depressed and, while not immediately suicidal, seriously wondering how I could possibly live for another 30 or 40 years in such pain. I was terrified that if something didn't fix the pain, I would be checking out prior to the four-or-five year mark. I had 24 hour a day pain -- PF in both feet -- and overall (I actually timed this), I spent about 21 or 22 hours of every day off my feet. Sleeping was the ONLY time my feet didn't hurt.
I am NOT cured. I still have PF. But -- I am walking easily 2.5 miles a day, and CAN walk up to 4 miles if I do it in two shifts. I basically go about my life pretty normally. I can shop, I can walk, I can vacuum, I can meet and talk to someone and stand on my feet for upwards of an hour. I can do all the stuff that I didn't do for a year and a half while I rested my feet and worked on them.
Do consider Birkenstocks. That is ALL I wear now. I have 10 pairs and I am prepared to live the rest of my life in Birks. They have magnificent arch support. I know you think you need cushioning and flexibility -- but mostly what your feet need is support. Marti is right -- it is critical to be fitted properly with Birks. But -- truly, I can't recommend them enough. I don't know where I would be without Birkenstocks. Believe me, when you find a shoe that alleviates your pain, you get over, real fast, not caring for the looks of them. In fact -- they look like the best shoes you have ever seen. For most folks they take some getting used to -- but truly, the arch support is excellent and you definitely get used to the hardness.
By the way, I also take Bromelain (heavy doses) and I stay on a self-concocted low-carb diet that eliminates caffeine, sodium, wheat, flour and sugar. That means no bread, pasta, cereal, real coffee or any of the other good stuff I love. But -- it truly makes a difference. Other than that, I don't take anything or do anything. No stretching; icing only after I walk, moderate rest for my feet -- just Birks, bromelain and a rigid (boring) diet. (I am, however, currently experimenting with lemongrass oil and that seems to be having a modest effect. Need more time.)
Maybe Birks won't work for you but I truly think they are worth a try. All I can tell you is -- honestly, a year ago at this time, I was in agony. I didn't care if I lived or not, if I was forced to live in that amount of pain. Today, my discomfort is minimal if I behave myself (and I do). I owe much of it to Birkenstocks.