You find it fascinating that other people think you're wrong? It's really weird that you're trying to act like the David Attenborough of Mumsnet and are directing your thoughts at some imagined audience.
You: If we look closely into this thread, we can see the internalised misogyny appearing. What a fascinating display.
OP (and others): "Actually, I'm just saying that some women are extremely selfi-"
You: "AS we can now see, the misogyny is internalising in real time. Such a special moment for us to capture here on Mumsnet. Utterly fascinating."
😐
I'm a woman who thinks a married/'taken' man, with or without children, is an unattractive prospect. I have never slept with someone's boyfriend, or husband. I think that shit is grim, and I've called men out who have tried to cheat with me. It genuinely makes me angry that they're such selfish idiots who are trying to inflict themselves on me, and could hurt their girlfriends badly for some meaningless titillation. I've always been this way, not because I've been hurt.
However if a man is single and I want him, I don't care about the competition, and I won't bow out just because someone else wants him. As soon as it seems like he' struggling to make his choice, or might prefer someone else, THEN I am no longer interested. Just naturally, easily, uninterested. And I'd respect his choice, and her, by not behaving as a threat in any way.
There are lots of people like me around, and I don't think it's misogynistic to say that women that aren't like this are extremely selfish.
Extreme selfishness is disgusting, whether that comes from a man or a woman, by the way. It's okay for OP to find her disgustingly selfish ex and his disgustingly selfish girlfriend utterly deplorable. Neither of them care about the well being of others, and that isn't just standard human behaviour like you're trying to make out.