You ain't sure; even when the situation occurs and rise to the
occasions, you wouldn't know as well. I always believe when a
relationship is gone, there is often very little reason why you
should get back together. For those rare occasions, there could be,
but generally from the cases I encountered - no. 
In the first place, if you desire to get back, why break and walk
on separate path? Worst if she is the one who initiated the break -
sure she is willing to get back on you? 
Thinking too much isn't good? Well, for your mind and your body
that is. No ample amount of thoughts towards matters of the heart
is enough - there is always so much shit that your wandering mind
always unconsciously ponders about. 
Advice? 
You may like to meet her. If possible, date her out and spend one
entire day with her. From there, you can find 60% of your answer.
Don't expect anything, just keep an open mind.

Cheers [/i]