I am no expert on this matter, but I understand that 1054 is largely a textbook date. Doesn't mean the mutual excommunications weren't important, but:
"Even after 1054 friendly relations between East and West continued. The two parts of Christendom were not yet conscious of a great gulf of separation between them. … The dispute remained something of which ordinary Christians in East and West were largely unaware"." (HE Kallistos Ware, in book chapter archived
here).
HE goes on to say, as many sources do, that the looting of Constantinople in the Fourth Crusade really made things "official."
The
Massacre of the Latins a couple decades earlier also did not help unity.
So while you may find a source about the formal break in communion with Rome, I think you will also find, the deeper you dig, that the problems started well before 1054 and that things were not, or at least did not LOOK, quite so dire for a century+ after 1054.