Hi Cynay,
If your name is on the credit card and you are responsible for it I would have that changed,seperate yourself from it. Put it in her lap. It's important not to let her walk all over you even though you want a relationship with her. If she has moved out because of whatever her reasons are then why should you be supporting a credit card?
Take some time before confrontiong her and after a few days or so you'll probably find you don't want to confront her. Do what you need to do to take care of you, sanely.
Good luck with it.
Ngaire