Wow, that is a lot to take in all at once; no wonder you are feeling overwhelmed! It sounds like you really could have used some consistency in Ginger's behaviour right now, and that not having that has really added stress to an event that already is unfolding in a way that doesn't match up with your ideals.
I hope that today goes okay, and that you and Ginger are able to reconnect in a meaningful way before the day is in full swing. I have witnessed you really struggling with some of his choices in the past while and my heart goes out to you. Broken agreements and selfish behaviour can be very emotionally taxing on one's partners and I know those feelings well.
Sending you love and strength, and wishes for a Happy Mother's Day Mags!