system
Given the following post, respond as if you're commenting on Reddit:
human
(GOT/ASOIAF) What if Robb Stark just gave up the war?

Lets say that shortly after executing Karstark, Robb decided to cut his losses and fully retreat back to the North. How would events play out from this decision?
gpt
If he just gave up and went back to Winterfell, he would have lost the support of all of his bannermen and lords who felt that they were fighting for a noble and worthy cause. He would have been alone in his castle (well, as alone as a major lord can be) when the Lannister armies arrived to execute him for treason. There's also a good chance the men who had been fighting for him would join that army both to keep themselves alive and get revenge on him for abandoning their goals. 

There really isn't a way Robb survives the war. Either he is betrayed or he betrays everyone around him and pays a bloody price.