Soooooo, as predicted, Mary is not interested in moving forward or smoothing things over. She replied to my above email. I'm going to paraphrase since I'm not sure about whether it would OK to quote her:
Again she launches in without preamble or greeting.
"It's not just one thing going wrong but things working against each other. There was at least one of my emails and maybe an email list post which weren't answered. And it's not just me. And when some of the people involved in the event are already being testy, I'm not going ask again and again. This is all just more proof that you can't depend only on the internet for communication when putting on an event. I know if I were in charge of an event, I would be making phone calls to contact people.
Mary"
The tone of this letter is actually less hostile than the first one she sent me.

I just want to say that I know we weren't perfect in every detail in running this event. I don't want Ehellions to think I am taking umbrage at the slightest criticism and refusing to hear that there's need for improvement. Many times after an event I've run, we hold an event wrap-up meeting where we go over in detail what went right and wrong at the event, and try to figure out ways to improve it for the future - and in fact we have a meeting set up for that purpose in a week. I definitely have screwed up sometimes, and I do want to make amends when that happens.
But I went (again!) through my emails and the posts on the list. Mary posted just 5 times in regard to the event, and was answered every time. I don't have *any* personal emails from her on the event at all. Sandy and I *did* fail to re-contact Mary when several weeks went by without her responding to Sandy's question about the item, but I have no evidence that Sandy was "testy" with Mary in any way. Sandy *isn't* usually testy or crabby, and actually it's Mary who's known for being grumpy and hot-tempered and flying off over nothing on a regular basis.
In the month before this event, I wrote more than 200 emails and posts to lists. I did make phone calls, at least 20 of them. I spent probably more than 100 hours of my time organizing this thing, and last weekend was hell, almost constant work. I'm still fighting a flare in my health problems, and stress exacerbates that (thank you, Mary, for adding to that!). Mary did almost nothing for the event - she taught a class. I'm not sure that she did *anything* else.
I've run over 30 events in the 25 years in my hobby club, some ranging up to 600 participants. In the old days we didn't have email, everything was by phone. It definitely took much more time, there were more mix-ups due to misunderstandings and the fact that things were not written down, and it certainly didn't ensure that people were always contacted - that still depended on the people.
And I just want to say to her, if she felt that email communication wasn't working, that Sandy or I didn't respond to her email or post, why didn't *she* pick up the phone and contact us? The phone works in both directions!
I'm sorry, I am feeling frustrated. I need to figure a way not to give Mary space in my head anymore.
Should I bother responding to her reply, or just let it flop on the floor?
Many thanks to you all for listening.