Try the Council of Florence. Rome has always sought union with the east. What she has been unwilling to do is abandon the beliefs that she has held since apostolic times. Argue, as other Orthodox here do, that these beliefs are wrong but let us recognize the desire for unity on the part of Rome, if only on her own terms (just as the Orthodox seek it on their terms).
In fact, Rome had been separating itself from the rest of Christendom for some centuries before the schism occurred. The excommunication you talk about only formalized it.
This was not the opinion of the bishops in the east that maintained union during all those centuries.
It may not have been their opinion, but it is a historical fact. Just because the rest of Christendom tried to keep Rome from removing itself doesn’t mean they weren’t aware of the western efforts in that direction.