In retrospect, a blended approach would have been better. That email was (mostly) emotional venting. I should have let this sit in my draft folder for several days until I cooled down a bit (even though I'm still very disappointed).
She said she spent two sleepless nights dwelling over this, and that she wanted to go, but at the time, these came across as feeble attempts to placate and diffuse the sting of doing this to me at the last minute.
I haven't heard from her since I last texted her on Friday stating I was going alone (which hurts given had I done this, I'd want to at least see if my spouse was having a good time).
I'm 'guessing' she's hurt and/or angry over my email hence no contact.
Next step is to decide if/when/how to initiate contact and what the message will be.
A couple of comments from a female friend still resonate:
"If you keep letting her act in this manner without consequences, why would she ever stop?"
"Don't you deserve better than this?"
"Don't you think it's a bad sign that you can't ask your wife what you are to her and talk openly about your marriage?"
"Does her behavior seem out of character?" [No.]
Me: 46 Ex: 38 Married: 10 Together: 12 No Children Separated (again): 09/06/13 Divorced: 02/27/15