So, she says 'you have faults too.'
IMHO, that is a classic A tactic to take the focus off themselves and whatever they are doing. They say it 'cos they know that you will buy into it and feel somehow inadequate or undeserving or guilty. Then you will think that you can't have expectations of them 'cos of those faults.
I've been listening to my ASO tell me that for years. As a result, I kept thinking that I couldn't have any expectations of him 'cos I wasn't, um, perfect! Now I'm starting to think that that is pretty silly. Sure, I have faults but mine don't involve endagering my child driving under the influence or spending money we can't afford or keeping illegal drugs in our house and car.
You sound as if you are beating yourself up and taking on a ton of responsibility for your AW unecessarily. All the other comments here about you 'holding her together' make sense to me. If you're not in love with her and her behaviour is insane, maybe you need to hold onto those two facts as you decide what to do, instead of worrying about how your behaviour (faults) might affect her.
Be kind to yourself and do what you need to do for yourself. She is definitely doing what she thinks that she needs to do regardless of the consequences for you.