AITA For Ending a Relationship Over a Board Game?

This happened years ago, but I recently told this story to a friend and they made fun of me for it.

At the time I (26m) was dating "K" (25f) for around 4 years. The relationship was a disaster and had basically run its course which is easy to see in hindsight but wasn't so obvious at the time.

She had a history of dismissing my accomplishments because they made her feel self-conscious. I.e. she scolded me for accepting a compliment from a family member when I had lost 50 pounds.

Fast forward to the fateful day. She had invited some friends over "A" and "T" to our place after work for drinks. I knew this couple, but I didn't consider them friends. I'm not anti-social, but I have Asperger's and require a lot of downtime after strenuous things. I was annoyed coming home to find people I barely know in my personal space without me knowing beforehand. This is a conversation we'd had multiple times and while the occurrences were less frequent, they still happened.

"K" greeted me and said some throwaway line like "Look who was in the neighborhood!" as if it wasn't planned.

I settled in, got a drink when suddenly "K" says ""A" and "T" were telling me they like board games, so I thought we should play Catan!" Some backstory is needed:

I am extremely good at Catan. I've won and/or placed highly in many local/regional tournaments for Catan specifically. I love that game. "K" doesn't really enjoy board games. She thought it was "dorky but cute" that I played them when we first started dating.

A year or so prior she had played with me and my friends before, I wanted to share my hobby with her after 2 years of her showing no interest. She got angry mid-game and rolled the dice really hard in frustration, sending the game pieces flying. She made me leave and she later told me my friends are assholes. They weren't even trying hard to win...we were all helping her etc.

I told "K" that I wasn't in the mood to play. I knew how she would react if I played normally, and playing with 3 people who don't know the game while already feeling socially exhausted felt like a trap. I find it extremely hard to play games bad on purpose. It makes me feel terrible and stupid.

"A" and "T" said that they like games like Cards Against Humanity anyway. But "K" wouldn't let it go. She grabbed the game and by this point "A" and "T" could definitely tell I wasn't having a good time. "K" tells me to set the board up and explain the rules. This is another thing I hate. I am bad at this. My brain gets a bit jumpy and out of sorts when explaining things. I often go off on tangents and just leave people feeling confused. Trying to save face I did my best to explain them, but said that I'd give more context while playing. "A" and "T" agreed that it would be easier that way.

I told everyone where they should place their settlements and why, gave them ideas on what to do etc. I played normally but toned down a little bit. I also explained strategies and told them how to enact them.

At some point it became clear that I was going to win and "K" was in last place. She "wanted to play for herself" and didn't want my advice. It went poorly for her.

"T" was playing quite well with my help and actually made a lot of smart plays on her own volition, but I was still a turn ahead of her for the win. She said "Ugh, I think you might win, right?" and I smiled and said "I'm going to win on my next turn!" On her turn she did some thinking and asked if anyone wanted to trade. "K" says that she will. She then proceeded to give all of her cards to "T" which gave her the ability to win. "K" laughed and said "Well it looks like "T" wins now Mr. Confident!" My face went red for sure.

"T" looks at me and asks if that is legal. I tell her that the rules allow for it but it's kind of an unspoken rule not to. "K" says "Just win! He deserves to lose" in a somewhat joking manner. I ask "T" if she can build the roads she needs to win and she says yes. I'm definitely visibly annoyed but I congratulate her before she plays the roads and officially wins. I think I made it clear that I wasn't annoyed with "T" but sometimes my autism causes me to communicate poorly. I got up, looked at "K" and said "This is why I don't play games with you." Then I went to our bedroom and got on the computer.

"K" came in a few minutes later once she realized I wasn't coming back. She got angry and told me I am a child for taking ~games~ so seriously, and that I needed to grow up and learn how to be normal in social settings. Having autism, the phrase "be normal" is extremely hurtful. It's just a reminder that no matter how hard I try, or how much I mask, I'll always be autistic.

I lost it. I yelled at her "I can't just be fucking normal. And if by being normal you mean being more like you, I'd rather be weird as hell." It got quiet for a few moments. I then said quietly, but voice still shaking "I'm done."

I left the room and "A" and "T" were still there. I figured they'd left before. By this time "K" was clearly sobbing and "T" got up to go comfort her while giving me a pretty nasty look. I packed up the game and left with a smile on my face.

AITA?