AITA for refusing to attend my best friend's wedding because of her fiancé's actions?

So, I (19F) have been best friends with "Jess" (19F) since childhood. We’ve been through thick and thin together, but recently things have gotten tense.

Jess’s fiancé (21M) has been openly rude and dismissive towards me whenever I’m around. He’s made some hurtful comments about my appearance and even mocked me for my career ambitions. Jess has defended him every time, saying that he’s just joking or doesn't mean it.

A few weeks ago, at her bridal shower, he made a comment about how I “could never be the maid of honor” because I “don’t have my life together." I was really hurt, and I told Jess I wouldn’t be attending the wedding if he was going to be there.

She got upset and said I was being dramatic and selfish. Now I’m wondering if I’m overreacting, but I honestly can’t be part of the wedding when I’m constantly being put down. AITA for not going?