BTDT
When was the last time you tried to reason with her and got somewhere? It may have happened at some point, but probably not very often. She's not interested in the same type of cohesiveness that you are, she's interested in winning.
It doesn't matter what her level of awareness is. She's a grown up and can be/needs to be responsible for herself. Part of codependency is accepting that other people have to deal with the natural consequences of their choices and behaviors. You can't control her, nor shou!d you. She is either good to you and your kids or not.
Even acting normal is part of the manipulative pattern. Think about a three year old who acts out and then adjusts accordingly to make sure she doesn't lose mommy's love or protection.
The best thing I ever did was to quit trying to engage on some deeper/ reasoning level. I take him at face value these days and don't respond based on history, but rather in the moment- much like a room mate or stranger. This approach is especially helpful to avoid getting baited into old, circular arguments. I know, easier said than done, but with time you can establish the new pattern.
In codependency, they also say that if you find yourself focused on the other person, you need to stop and ask yourself what you want instead. Unfortunately, many of us don't know, so we keep focusing on the other person

. Like your buddy said, if you can stop thinking about it for a while and go do something with your kids, do that. Have fun! You deserve it. Even if you don't feel like doing it, maybe start going through the motions and see if you get into it. Your kids will appreciate it anyway.
You are probably dealing with a very long history of being covertly manipulated and gaslighted. She knows what she's doing even if she doesn't know what she's doing. It's hard to trust yourself after that because the person you trusted the most isn't suppose to do those things. Journaling events helps me because then I'm able to keep track of ongoing patterns, and that helps when I'm feeling knocked off balance. Just spitballing here, but like you, I grew up in a very unhealthy family. Terrible things happened and there was nothing I could do about it but put it in the past and keep going. Unfortunately, I have a habit of doing that in my marriage. He can be a total jerk, and the next day I've moved on. It's one thing to be forgiving, something else entirely to be a chump. Like I said, making notes has helped me to remember the patterns that are unacceptable.
Hope you go have some fun this weekend, you all deserve it.