Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: Okay so some context: me and my boyfriend have been together for around two and a half years now and his birthday isn't for a few months but his mother has already started to plan a surprise party for him and his step brother to share (who will be turning 21) the 21 year old likes Anime and my boyfriend likes Pokémon(however his mother is convinced that he also likes Anime) so she themed the party 'Pokémon Anime and everything japanese' which itself is a bit cringy and people are going to be cos playing from Pokémon and Anime of they wish.

Now the other day she told me she was making him an outfit for the party and to be clear this boy has never shown an interest in dressing up, even for Halloween he didn't want to dress up. I was starting to get worried so I messaged my boyfriends bother as he knows my boyfriend well enough to know its not something he'd like, but get hit back with a lot of aggression saying that I was being negative and that if we can't have fun it's more of a reflection on our personalities rather than the party (I never said anything about fun I was saying that my bf wouldn't like being forced to dress up) and thus that conversation swiftly ends.

Fast-forward to the next day and my boyfriend joins my party on Xbox when he gets back from work and tells me I'm not in his mums good books and I find out that she told him about the surprise party just because of what I said and because I was in her bad books? Which I thought was kind of immature as she could have messaged me herself but I'll let it slide. So my boyfriend then questions why I would ask his bother as 'I should know that once his mum is convinced of something, no one can change her mind'. I still don't understand what I did wrong. 

AITA? 

trying to sway bf's mother from forcing him to cosplay for his 18th birthday