You bullied her (Male)

It was unfair but you've done some mean things to Zoe in the past after your friends encouraged you too. Calling her names, laughing at her and gossiping about her behind her back. But this was a year ago! You've changed after you realized how immature you were being and tried to just stay away from her as much as possible.

Sure you've never exactly apologized, that would be awkward. It's not like you said anything untrue anyway. But yes, how she always visibly recoils when you look at her makes you feel awful... but you don't know what you can do about it if anything.

While avoiding her for the past few months seems to have worked, it seems fate has destined that the two of you will be together today in a very awkward situation.