Yo, I feel this! About a month and a half ago there was a big dance that i've gone to several times in the past and was looking forward to. It was sort of a looming date on the calendar after she went NC in Dec. because I knew i'd see her there. I was worried about seeing my ex, how she'd react, whether she'd be there w/ another guy, whether we'd talk, etc. I also had a paper due the week after so i decided not to take the emotional risk and try to get some work done on my paper. I didn't end up going and I think it was the right decision. I really need(ed) to keep my head as straight-as-possible w/ school and I think seeing her would've put me back into a bad state (assuming we didn't have reconciliation).
Good luck!