Tbm, I'm not the most experienced but it sounds to me like you are too worried about what your W is doing. I've made this mistake and it brings a lot more worry to your mind than you need. If you didn't want to bake the cake I think it was fine to say but I think you should have stuck to it. Sounds like you folded when she went nuts and I can't say that helps either. From what I've heard, choose carefully when to draw a line in the sand but hold the line if you do.
I can't say I disagree with the comment of control. I could be totally off base, and apologize if I have it wrong but it sounds like you said that because you didn't approve of what she was doing with her time. Not because you didn't have time or want to bake the cake. I think if you can't get your mind off what she is thinking and purely on what you are doing, this space between you can only get bigger or stay the same.
M: 43 W: 43 Married 6 yrs. T: 7 yrs. Son 20, 18, 17, 15 yrs. (w/ Autism), 12, 10