*I know what you are getting at. The flip side of this is that there is a lot of "women aren't responsible" for men's cheating when it doesn't quite work like that.
That women in that moment has a choice to be complicit in something that she knows will cause hurt to another person, something that is deemed shameful by society (the cheating not the sex) and she choses to do it anyway. We have to give women some agency in these situations. Also translated as responsibility.*
I would say that women are responsible for her choice in the situation, however not responsible for the man cheating. To be responsible for the man cheating would mean that they had caused this man to cheat, whereas the likelihood is if it wasn't this women, he would have gone after another.
She was responsible for being complicit in the act but did not cause this man to cheat. He did that.
I know some people will say they would think the same regardless of if the genders were reversed, and yes lots of people would, however it would be incredibly nieve to think that, in society as a whole, a man who sleeps with a hen is treated with the same level of derision as a woman how sleeps with a stag.
I am in no way defending what this woman did, however, I will challenge certain words, name and phrases when I see them used, as these phrases do feed into an unhealthy narrative, even if said without meaning to.