AITA for throwing water on my friends wedding cake?

I was a bridesmaid for my friend and I was so excited! She is my closest friend. We grew up together. For the ceremony she wanted all the bridesmaids and groomsmen to put a pendant on our necklaces if we were judging people or if we were gossiping. I thought it was really weird but hey, bride’s day. <br><br>She was very religious and the ceremony was also very religious. <br><br>At the reception, my boyfriend was judging a lot of people. We hadn’t been dating long but the wedding was at a very inconvenient time and I couldn’t find a babysitter and he offered to come with me. So I had 4 pendants on my necklace already. <br><br>Just as we were about to eat, one of the other bridesmaids walked in with a truly heinous-looking man. It became apparent very quickly that this was the bride’s ex-boyfriend, who was also a sexual predator, and he was there to cause drama. <br><br>The bride and groom were arguing about if they should kick him out but I walked up to the table and dumped my water glass on the cake and said “I’m judging ALL of you.” The bride started screaming at me and the other bridesmaid was trying to get her ex out but I just grabbed my boyfriend and left. <br><br>They called me a few days after and the bride told me she couldn’t believe I ruined her wedding like that. The other bridesmaid called me and told me if it wasn’t for me, bride’s ex wouldn’t have been able to get in and do all the damage he did. Bride and groom did end up breaking up and other bridesmaid is now engaged to the predator so I only lost a friend. <br><br>AITA for ruining the cake?