what she means:
You can't tell me the whole Scranton branch didn't shut when Michael and Holly got married. That they didn't fly out to Colorado to see Michael marry the girl of his dreams. You can't tell me Michael didn't try to get Ryan to be his best man but when Ryan ran away, he asked Dwight instead. That Jim wasn't a groomsman. That Cece wasn't the flower girl. That Andy didn't sing the song Michael and Holly danced to. That Kelly and Andy didn't have another dance off and this time, Andy didn't have to go to the ER. That Phyllis, Pam, and Erin didn't cry when they said I do. That Michael didn't ask Erin for a dance. That the whole office didn't plan a flash mob like at Jim and Pam's wedding. There is no way none of this didn't happen.