Cancel the shared accounts as soon as possible, but do bear in mind that the funds in it will more than likely be split 50:50. Consult a lawyer on this one, but do take action, every day wasted can mean huge problems. As well as shared savings, shared debt is also distributed 50:50, so you can find yourself in a lot of hot water really fast. Try explaining to the banks that you were "separated" when the debt was accrued, they will not give a flying fcuck. MArried on paper, you are responsible for debt. Period.
Again, do not wait, act! Procrastination is the mind killer.
I know you are afraid to make waves. What is she going to do? LEave you again? LEt her leave. You cannot stop her, and why would you want to? The best favor you can do to yourself is to release that that not want to be tied to you.