The cold is considered incurable although it has a treatment. Does walking pneumonia fall in this category? Someone I know says they were told the bacteria never leaves their body, and so they have walking pneumonia for life - I thought unlike the cold this was a curable disease.
Fortunately "walking pneumonia", also known as atypical pneumonia, is not a lifelong condition. Atypical pneumonia can be caused by various bacteria and viruses. The most common bacteria that causes atypical pneumonia is Mycoplasma pneumoniae.
From the CDC:
"Most M. pneumoniae infections are self-limiting; however, clinicians routinely treat pneumonia caused by Mycoplasma pneumoniae with antibiotics." Two of the most common antibiotics used to treat atypical pneumonia are azithromycin and doxycycline.
It sounds as though you may be misinterpreting the term "incurable". While it's true that respiratory infections caused by a virus don't have a drug that can cure them, this does not mean that you have the infection for life. In the case of a cold and the vast majority of other viral respiratory infections, including viral atypical pneumonia, your own immune system is able to mount a response to the virus and eradicate it. When this happens you are cured-- no medication necessary.