Yep, you guys need to work on your communication skills between the three of you. When you do push for the meeting, make that the focus. "Hey, this thing with the wedding just illustrated that we need to work on better ways to communicate and get our point across without misunderstandings". Even a professional counselor could be beneficial with helping the three of you communicate better. I wonder if she waited to the last minute, because she WANTED to be okay with you being there, but with all the wedding stress, she just freaked out.
Now (communication issues aside), you suspected she would have a problem with being "outed" and you know you have trouble controlling pda you could have spent all those months LEARNING how to interact in a public setting, where everyone would be comfortable. Short little dinners with just the three of you where you could PRACTICE not showing pda. That way everyone would be confident that they could behave in a manner that wouldn't cause an uncomfortable situation.