Ok, I'll explain it: Pastor Galswells said he was going to help her just so she wouldn't fight when they got to her house. Basically, he lied to her because he thought she was insane. I'd think she was insane too if she'd exist. No one can marry a dead person...in real life.
What thetscfan121 said.. He lied to her so she would go back to the house. He was afraid that she had gone insane and wanted to protect her from herself, so she was locked up.
He betrayed her yes in making her trust him, but he only thought he did was best for her
So she didn't play along, she honestly thought that he would help her