I completely understand her fear for not wanting to open up at meeting, as the underlying problem of abuse (if I have understood correctly) means that the AA isn't the place to discuss this. She sounds like she needs a counsellor that specializes in abuse.
With the other situations you have mentioned, It sounds like she is on 'self-destruct' she is seeking oblivion. Alcohol is an 'intoxicant' - it is 'toxic', poison. I have had 3 very good friends lose their parents over drink and they have never got over it.
Her family telling her to pull herself together is a typically british response, its just another way of not dealing with it and not wanting to. Sounds like she is not allowed to have any feelings. Do you know if the abuse was linked to the family? Do they know?
As long as she doesn't like the idea of opening up, the longer she lives with the pain inside, the longer she drinks to soften the pain. The longer the pain she passes onto the next generation and so on.
There is a lovely book called The Prophet by Kahil Gibran, and there is a line in the book which goes: "Tell me about pain" and the reply is "Your pain is the braking of the shell that encloses your own understanding". If she is allowed to have feelings including the bad ones then she might have the oppotunity to look at other choices and other coping mechanisms. Treatment may be able to teach her new coping strategies.
Four children that's a lot of sadness to carry on little shoulders
The rot has to stop. Phone her dh tonight and see if you can both start things moving now.