Caught My Partner Cheating in the Darkest Way Possible

I can barely bring myself to type this out loud. It feels like I'm reliving it every second. Last week, my partner, who we're both very open about our polyamory and having multiple connections, was supposed to be spending a night with me. But when she didn't show up until midnight, I got worried. Turns out, she'd been at some underground BDSM event downtown, where she hooked up with someone else in the most... intense way possible for hours before coming home. She admitted everything that morning. The details were so explicit and graphic, she described her encounter vividly as if it was a fantasy novel come to life. I felt sick hearing how they explored each other's bodies, exploring every inch of skin and muscle with their hands and mouths. There were no soft edges here; she talked about hard thrusts and rough play that left marks behind. I tried not to let it affect me too much but seeing her so unapologetic was tough. She said it felt freeing, like breaking the rules brought a new kind of intimacy. It's made me question everything we have together, how open can I be without feeling like this all the time? Am I just being too sensitive or is something really off now? The rawness and intensity of her confession has left me reeling.