I don't believe Micah ever intended to go through with the marriage at any point.

1. Her behaviour in the pods was childish, nasty and manipulative.
2. The way she spoke about and at times to Paul, like he was a project. His clothes, his flat.... Like a child expecting her way or not at all.
3. How she continued talking to her "friend" after said "friend" was blatantly rude to her fiance.
4. The way she acted walking down the Isle.... giggling and talking and making jokes.
5. The very low effort she put into the wedding. Her dress looked like she was attending a formal event. She didn't look at all like a bride. Hair, make-up, ill fitting dress that was falling off. It's like she didn't care at all.
6. Manipulating the situation asking Paul to go first. Even if she did suspect he was going to say 'No', she should have answered as the officiant asked her first.

My take is that she knew things weren't great between them, so she thought she'd come out of it smelling like roses if he said no first and she could victimise herself. She put no effort into her wedding day cause she knew it OR hoped it wasn't going to end in marriage.

I keep thinking about the day they met her parents. The whole way she relayed the engagement and wedding details to them was odd like she was taking it all so lightly. No seriousness at all.