My bsf cheated on her bf with my bf's brother...

YES I KNOW THIS SOUNDS CRAZY.

So i was just in my room, day like every other and then she calls me. She's like ''we broke up blah blah blah'' so i ask why and she said that she cheated on him. Like girl, okay, you do you, idc, but i ask with who and like you can read from the caption, IT WAS WITH MY BOYFRIEND'S BROTHER. and that one blog where i said she was hitting on my bf? SHE SAID SHE THOUGHT IT WAS THE BROTHER (i mean the guy she was cheating with i don't wanna call names) i mean they're sibling and they look kinda a like BUT GIRL MY BF'S EMO AND HIS BROTHER IS THE MOST BASIC GUY EVER. Idk how drunk&high that girl must've been because honestly- what the fuck. What's good at least she wasnt cheating with my bf but still