Roll with it
Bigboy .. you just have to go with the flow. If you know that her emotions and attitude is much different than it normally is, when she's not expecting, then you have to give her the benefit of the doubt. Put your ego aside, and let her be who she's going to be. Don't put up any resistance. It's kinda like teaching your kid to ride a bike, you give them a little push, then you have to stand back and just do what you can to make sure she doesn't fall.
That's what you have to do with your spouse, just stand back (you've already given her the 'push') and make sure she doesn't fall. If she makes a decision and you know it's emotionally charged, step back, don't fight her on it, and most of the time, if she has time to think about it, and you've put up no resistance, she will realize that she's not made a wise decision and either correct it, or you can go behind the scenes and correct it.
Here's a little example, my ex-wife was a pack-rat, wanted to save every box we got. Initially I would debate with her own it, and she was adamant about keeping the box. What I learned was, don't fight her on it, put the box in the garage as she wished me to do, then, 3-4 weeks later I would throw the box out. No argument, she never realized the box was gone.
If you're wondering why we didn't make it, as I have mentioned, "ex-wife", we were not compatible, but I learned a good deal about being married and about women in general. I have also been able to raise my kids as well, so I didn't have to assume the "every-other-weekend" role.