Constantinople

The Latin Empire gets massive aid from the West and manages to survive. The Byzantine re-conquest of 1261 never happens. How long can the Nicean state survive?
 
They possibly could've began to take out the rest of the Byzantines in Greece and what not and than the ottomans could've taken out the eastern Byzantines then maybe in the future a ottoman-Latin empire war with the support of the west?
 
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