Hi graynimo, just to provide some opinion, from my perspective,
ya its true that it would not last long this time, sorry to say. As
you mentioned above, he “took picture with a girl” and posted on
facebook for everyone to see, during the “Cold War” term between
you 2. This is an obvious hint already, and disrespect. How can
someone who just broke up go filrting around with other girls?? Its
like he doesn’t even need time to recover like that…
Sorry to say this, although i know that we as by-standers could
not feel how the person involved feel exactly, but perhaps its
better to let go. Maybe if you let go now, you 2 can still stay as
frens before things turn ugly as you start to speculate about his
actions, like “why is he like that?” “why is he not replying? is he
ignoring me again? ” As such war may break out again if you become
over controlling or obessive and this time there maybe much more
arguing and fights and it ends sour.
If both of you remain frens now, perhaps in the future when
things are different, when you both are even more mature and
experienced in life, if it means to be, there may still be a
chance, a better one.
Cheer up! SG needs more happy girls 
StarryLight11