Old ass thread, didn't read the replies so I hope nobody said this, she got "raped" when they where dating, was close with the dude, didn't actually put her foot down, got drunk and put herself in a precarious position at the mercy of someone she knew had interest in her.
Or perhaps she had two drinks, fucked the dude and made the whole thing up to make her cuck boyfriend happy, like most rapes, ima assume there was no witnesses, no police report, and for some reason she doesn't want to disclose the guy who did it.