Do none of that and just GAL. Let her do her thing, but let her know that you will be separating the accounts and yadda yadda yadda. Don't do it angrily just explain that she chose to do this and this is just another natural step in the decision she made.
It will hurt but you need to show her you are strong and do not need her.
Remember she needs to see the consequences of her actions. If you confront her it will just embolden her.
