The MLCer HATES, HATES to be told what to do. Even if you know your family's financial reality does have an impact on the family's spending patterns. So you telling W to "wait" on certain expenses after the bills are paid is to lecture her...that is how it is in her MLC mind.
You may want to try to have a financial spreadhseet that shows flow of incoming income and outgoing expenses to show W. Then again, it's NO GUARANTEE that she'll listen to you. It is because of this behavior pattern in MLCer that we all encourage the LBS to set up a separate account to protect your financial interests...that means separate credit card accounts, bank accounts, and whatnot. We've seen the MLCers around this board spend money like there's no tomorrow and flows out of the bank account(s) like water.
Don't worry or take personally what W tells you. It will change maybe 50 times a week. That is the crazymaking that the MLCer will do that drives the LBS batshit. Detach.
Continue focusing on yourself. Do things that you LIKE and ENJOY doing....hobbies, interests, and activities. Act like you two are housemates living in different spheres.
If she says you're lying or whatnot, just say:
I am sorry you feel this way. I am going to continue doing what I enjoy. If this bothers you, you will need to figure this out yourself.
Keep going on your own GAL activities. If you keep looking backward, you're bound to hit the tree head on. Wouldn't want that, do you?