Jods, there is no medical cure to PTSD. Exactly what has already been stated above, with some very good points raised.

Think of cancer, where you can go into remission, though after 6 years or something, if no more cancer returns, they call you cured, however; two years later again, more cancer could arise.

The problem with PTSD though opposed to physical conditions, is this is a mental condition, and a mental condition not caused by simply our brain rewiring itself because it wants to, but our brain rewiring itself because it has been exposed to a significant traumatic event. Not just a traumatic event, ie. death in the family, etc, but a traumatic event to the point where your life has been threatened, at deaths door possibly, or your integrity has been threatened from prolonged abuse over many years, ie. constant bashing, physical and mental abuse, etc...

Memories never go away, they never physically disappear like cancer can, they are always with you. Coming to terms with those memories and no longer fearing them, is a positive step forward and you can learn to reassociate yourself within society with little recourse from PTSD itself, however; one simple thing occurs, and bam, suddenly a memory is triggered, what you fear comes flooding back, and at this point you decide what happens, ie. you cope with the memory for what it is, a bad memory of your past, or you take that memory and become depressed, then anxious, then panic, then dream about it, then dwell upon it more, then start drinking or doing drugs to try and suppress the memory, then your on a downward spiral once again into the realms of PTSD. If you take that memory for what it is at the time is recalls, you work through it, you use all your self techniques you have learnt or adapted to suit yourself, and then suddenly the memory dissapates again along with all the sudden symptom outburst, and within a day you back to your normal life, except now you just found another trigger in which you may have to work upon to cope with next time it occurs, or you go and intentionally begin exposing yourself to such a trigger again to build a wall in response to it, where it no longer becomes a trigger, instead just an annoyance within your day, or reflection of the past, nothing more.

If a significant event occured within your life though, ie. someone you cared about died suddenly, accident, child, etc, then that could spiral you out of control once again into the deepest and darkest we are / have lived with PTSD. You could remain there for another year or more if you regain guilt from the recent event, blame, etc etc... you then manifest a recent trauma into a significant traumatic memory for you, thus you have to then work that traumatic event through to gain the same resolution once again.

Even when better, your mind will still try and overpower you every now and again, it will reraise symptoms, it will raise memories, PTSD does and will constantly make attempts to gain control over you, but with logical thought, support, discussion and technique implementation, you can keep it under control for the most part.

The thing with PTSD is that your life as it was, will never be again, instead a new normal will become, and it is this that must be worked upon, not how you used to be and the things you used to be capable off doing.