Women should not do anything unforgivable.

Anyhow what matters is that she does not have any bad personality traits. There are things women can do, like cheating, that is just unforgivable. Before you get on with her, you need to make sure that she would never do something like that.

Being tsundere is also unforgivable and there are many other unforgivable things.

Disrespect to me is unforgivable.

Valuing anything more than me is unforgivable.

Cheating on me is unforgivable.

Lying is unforgivable.