If you've known her for 9 years then you would have encountered a similar situation in that amount of time. Getting a diagnosis of DID wouldn't suddenly cause parts of her to magically appear
@OptimisticRealist - without a release, I'm doubtful the therapist could talk with you about your SO's therapy. But, you can tell the therapist things. If you are concerned that she is (unknowingly or knowingly, it doesn't matter) putting herself or her children in harm's way, then she may be considered of danger to herself, or others. Those would be grounds for emergency hospitalization.
It's a deeply upsetting and unpleasant thing to set in motion, I know. But sometimes the most caring thing you can do for someone is pull the emergency cord. Reporting her behavior to the therapist would be a good first step. Researching inpatient facilities would be a good second step. Consulting with a lawyer on the problem of the morality clause (as well as determining your own legal status in the relationship, if you're unclear) - third step.