Am I wrong??? Sex party nightmares

I was stating a woman who is polyamorous for three months. I really liked her and had feelings for her, but I made the decision to end things. She had six other ongoing relationships be beside ours, and I didn't feel prioritized or like I was in the kind of relationship I desired. As much as I loved being with her, I dealt with a lot of her outside of our time together that made it really hard. There was also a lot of drama in the early parts of our relationship that made me distrustful of her and made it hard to form a secure attachment.

She took me to a sex party for the first time on our third date. We went together several times while we were dating and had a lot of fun.

After we broke up, I don't have interest in going to the sex party anymore. However, my friends band was playing a show, and I had agreed to help and do photography for them.

I understood that she was going to have sex there, but it's such a huge venue. I figured she could do what she wants and I could leave if I didn't wanna witness it.

She insisted that she wanted to be friends. She said she wasn't angry with me, but there was some irritated communication. I told her I was concerned it might be awkward and she blew up on me.

The night of the show we said hi to each other, and she went off to do her thing. The show started and I saved a seat for her and invited her to dance with me, but she said she was busy.

Five minutes after that, she comes through with some guy and begins fucking him in the seat that I saved for her right in front of the show.

I didn't say anything to her that night, but we fought about it over text.

I feel like her behavior was clearly vindictive or attention seeking or both. The venue was so huge and the show was only an hour out of a five hour event. She knew that I was working and taking photography for the show and it felt like she just wanted to make me a captive audience. This project is also something that's really important to me and something after collaborated with for a long time. I also helped make the show happen.

But then she tried to gaslight me and tell me she doesn't know what I was talking about, she had no idea where I was standing, it's not a big deal and my reaction is crazy. I have no right to be upset. And I could've had her all to myself if I wanted???

I feel like I'm going crazy. I really had feelings for this person, but it seems like she didn't care about me that much and that's why I ended things. She insisted she wanted to make an effort to be friends, but this just wasn't friendly behavior.

I know it was a sex party and I expected her to have sex with whoever she wanted. I expected her to make somewhat of a jealous spectacle, even. But she knew I had to work and she knew the event was important to me. Also, eight of my closest friends were there.

Feels really shitty, but I'm being gaslit so hard right now. Am I wrong?