As bad as it hurts, sometimes when they do stuff like this, it is the end. They just don't have the emotional capability to end it properly. Shoot, it seems like half the healthy functioning males around now don't even have the emotional capability to end things properly and give a girl some closure.
You guys are breaking my heart... I can tell you are hurting so much. Would it be healthier in the long run for your own sanity to just chalk it up as "over" and start the healing process? You have to remember, sometimes when they leave, its because they leave... not because they have PTSD.
There are a lot of supporters on here whose sufferers have left them in the lurch like this and don't come back. It's not hard to find threads where supporters have been holding on for a long, long time waiting on their loved one to come back. Months, years... how long is it healthy to wait and not have your own life?
This is a hard part of being a supporter. The isolation periods, especially if they take off with no word and leave you doubting the status of your relationship, are brutal. Most supporters I know would rather be berated verbally than go through this hell. You have to make the decision though... how long are you willing to put your life on hold for something that may never be again?