So what if you are in a bad mood sometimes? Just like you, your W needs to learn to detach from this and not reflect it or personalize it. Just like you, your W needs to make some changes and do some personal growth.
It is B.S. that you have not changed and you both know that. Call her on such extreme unhelpful B.S.: "W, I'm very sorry that you feel that way. I'm somewhat at a loss -- I know I have changed hugely, even though I am not always perfect and I still have a lot to work on. But, when you say that I have not changed at all, I feel unappreciated, blah blah blah..."
W needs to stop managing your feelings, and you need to stop managing hers.
Also, and this is a big also, you need to quit assuming the role of sole-fix-it guy in the M. Why not say to W: "W, thanks so much for helping me see where I still have some work to do. It is so easy to fall back into old patterns. Can we work together to try to create new ways of doing things and living? What ideas do you have about how we can change the household dynamics?"
Remember, you are *partners*. Acknowledge the problem -- get clear about what it really is, when it arises, what triggers it, etc... Brainstorm together about solutions.
Now, as for taking things out on your kids, WTH are you to use them as your emotional punching bag when you need release? Maybe you can literally get a real punching bag and hang it up in the basement for such times (not being sarcastic). What are some other alternatives that are quick, easy, and readily available for when you feel your temper rising? This is definitely a good, identifiable project for C.
"W, the words "always" and "never" seldom apply to the dynamics of our R, and especially with what we are going through now. It would really help me be less defensive and help our dialogue in general if we both try to avoid using them. This will really help our communication be more productive."