What deems a stroke victim capable of making their own decisions and/or being transferred out of the Psychiatric ward to a reg room or discharge?

Stroke patients do not normally reside in a psychiatric facility. Was she in the psych ward before she had the stroke? Why was she admitted there?.
Depending on the severity of a stroke the sufferer may or may not be capable of making their own decisions and taking care of themselves. On the other hand others may loose so many of their abilities they become totally dependent on others..
Can you tell us more about the general condition of the patient and your relationship.

It varies depending on the patient. Ask the doc if you are POA or have a HIPPA release.