What happened between Gwen and Paedon?

I know there is bad blood between them, but is it so bad that they couldn’t put it aside for one day to both be at their Mom’s wedding? I didn’t see Gwen, and it just is so sad that they couldn’t both be there for Christine.

I know Paedon has some huge political differences with Gwen and has some negative beliefs about LGBTQ. There were so many people there, she didn’t necessarily have to interact with him at all.

Edit: Sorry, I thought she didn’t go because of the animosity between them. I thought I saw on here that she refuses to be in the same room as him. I must have missed the part about her exams.