thank you for your question,
unfortunately in some cases amputation
can be the only solution and make the life of the patient much better using limb prosthesis
I have seen many patients who had amputation and they are quite glad with their quality of life, at the end of the day if the foot is causing you significant troubles and pain, then it is unlikely to get back normal again.
having said that, you can always refuse the amputation and continue with IV antibiotics long term +/- local debridement (washout and cleaning of unhealthy tissue). but you need to check with your doctor if it is possible option and will not cause further spread of infection to the tibia