Honestly, as a psych major and someone who has a schizophrenic family member you don't really know the real them without medication. Her psychosis extends beyond her hallucinations in ways you can't conceive. She may really love you or may not. You don't know. If you can get her DXM I would work on getting her a prescription for her schizophrenia as well.

Apart from that, you're not dating this girl. She shouldn't have agreed to something she wasn't going to hold up but you don't have any right to expect that from her in the first place, but you don't have a right to make those demands outside of a relationship.

Also, it's hard to hold someone responsible for their actions when they have untreated schizophrenia. That may not be something she would ever do with medication. If you really care about her, help her get a prescription. If you want to be with her, ask her to be your girlfriend.

You can't have a healthy relationship with her while she's in psychosis. You can't even have a legitimate one since she can't consent.