Plantar fasciitis can be be extremely painful and can linger a long time. Its caused by abnormal pulling or stress that causes a chronic inflammation or degeneration within the fibers of the fascia.
Understand that I am answering your question without the benefit of examining you, but in short, it sounds like surgery is an option for you. You have had this pain a long time, and non surgical methods aren't working. If you are on your feet so much, a custom orthotic may be needed. I am not clear if you have one or not.
I treat fasciitis initially with stretching exercises, both active stretches and with something called a plantar fasciitis night splint, which your doctor may have or you might find one on the internet.
Shots are helpful but rarely curative.
A properly fitted total contact orthotic is the best treatment in my opinion, and I have seen greater than 93% pain relief in 3 months.
Surgery is not without risks and complications, and should rarely be a first choice.
The May/June 2013 issue of the The Journal of Foot and Ankle Surgery has an article that discusses a traditional from of surgery for fasciitis versus an instep fasciotomy through a small incision. The study concluded that the instep procedure resulted in better pain relief and less complications.
I prefer the instep fasciotomy when I do this surgery. Other methods include an endoscopic technique, which I have also done, but the instep procedure in my opinion is preferable. It still would require almost a month of down time if you are on your feet all the time at work.
Patients and doctors need to be comfortable with each other and the treatment plan. I always offer my patients a second opinion with another local doctor, and other doctors do so with me. Its a nice way to have another opinion without any concerns on either party. Sometimes the other opinion helps me rethink my approach.