I was diagnosed at age 49 and have probably had this since age 15 in varying degrees (much worse during stressful times in my life). When we develop ptsd early in life we tend to develop unhealthy coping skills. At least that's my situation. For example, I learned to suppress emotions instead of learning to express them in a productive way. Instead of thinking about it as never being the same again, you might want to concentrate on using CBT to work on changing the behaviors and coping mechanisms that are holding you back. I believe that you are correct in stating that we become what we are in spite of what happened to us especially when the trauma/s occur early in life.

I think it also important to note that ptsd encompasses a wide variation of symptoms and severity. Don't assume that you will develop every symptom discussed on this forum. Perhaps keeping that in mind will make the diagnosis a little easier to accept.