Oh my dear Aquarian,
I remember how anxious you were about this wedding, and it seems from your account that the nightmare you hoped wouldn't happen became reality.
I feel your pain and emotional numbness - but so admire your strength and tenacity to complete all the ceremonial functions from the rehearsal, welcome dinner, wedding ceremony, reception to a farewell brunch. That's an enormous amount of courage - in your shoes, I probably would have wimped out to being present at the ceremony itself only.
I cannot imagine the impact of the hurt and cruelty of your daughter ignoring you and even apologising for your presence ... my heart goes out to you. The malicious cruelty of your exh's actions to alienate you is par for the course with PDs' irrational focus on self in any circumstances, but that he has manipulated and brainwashed your daughter on what should have been her special day is beyond forgiveness.
In a way, I do feel so sorry for your daughter as well - that she too is an unwitting victim of her father's mental disorder and instead of a father's protection and concern for her wellbeing, he is using her as a tool in order to 'punish' you.
So heartbreaking on all fronts.
But as we both know, spouses with PDs have no hesitation to manipulate/exploit their children in order to have their needs met to achieve cunning emotional-abuse and denigration triumph in their primary 'adversary'.
I so understand that the rejection and emotional impact of what should have been a joyous occasion will take time to digest and work through, Aquarian - and with the support of your family and therapy, this too will pass.
I agree it's probably way too early to discuss what happened with your eldest son; give yourself time to recover first so that you are more balanced and in control of your emotions which are so raw just now - you say he "faces things heads-on and is very outspoken" and perhaps you need time to evaluate whether the repercussions of his 'outspoken-ness' could actually make things worse.
I do feel that your exh's rudeness and irrational behaviour at such a big gathering was probably noted by many more than you realise, so possibly there is more comprehension of the truth - in spite of him painting you black - through his own demonstrated immature behaviours than you realise.
My thoughts are with you,

Sealie