How long is it supposed to it normally take to recover from ptsd?

Very variable: People with acute, mild, simple ptsd may recover within weeks of starting treatment. However for individuals with moderate to severe, complex ptsd (especially with delayed treatment) it might be a lifelong disorder with sx control being the objective.

Management: Typically with the more severe cases of PTSD, the medical/psychological is not so much about curing it, as it is about effectively managing it. It never goes away in the sense of being cured. In a way both patients and doctors are students of managing severe cases of PTSD, and never master of controlling it, unfortunately.