We were supposed to go to the mediator this past Tues which I had forgotten about until she reminded me on Mon. I told her to reschedule it please because I had to work. I believe she just canceled it and blew it off or she went without me (I seriously doubt it) as not another word was mentioned.
Good for you for taking control of the situation. Your wife is free to make her choices but she can't control any of your actions. However, don't assume what your wife did. She may have gone to mediation without you.
I'm impressed how you handled the phone call. Very empathetic. You recognized she was disclosing intimate information--unhappiness with her life--and by doing this, she was handing over trust. You could have lashed out when she gave you this information (i.e. "You made your bed...now lie in it.")
But you didn't.
I think your response was very appropriate. You let her know it is okay to talk to you about her feelings.
I think sending the video greeting card was a very loving extra step. Again it validated her decision to trust you as a confident.