Right, but there's something about this that you're not understanding. The people in this thread are not talking about a real woman, they're talking about a hypothetical woman. A "reasonable person" kind of woman.
Yes, we could talk about how it's technically possible that his wife is on disability and is circumstantially incapable of leaving him, therefore she wouldn't, QED—but it's just not that interesting.
People are saying "she would leave him," but what they actually mean is "she should leave him." You don't realize that you're arguing with this second sentence, that's why you're chafing against everyone here. There's subtext that you're missing.