Siz wrote to Raz again. Her comment echos what you said, with a dash of self-loathing included as well.

I also agree that Hydra is justified in feeling the way she does. Sally-Anne, while she made a mistake, acted from a selfless place (trying to save Justin). Siz's relationship with Tosha has been for more selfish (and cerebral) reasons. I understand why Hydra would have no tolerance for that, after everything she's been through.