"She just came out of a coma. We live in Michigan. "
Generally, cannabis can help with headaches and nausea. Cannabis can also help with some of the side effects of chemotherapy and radiation such as appetite loss. High CBD has also show to help reduce seizures but this is all general and not specific for Glioblastoma. Cannabis has also show to reduce pressure in the eyes for Glaucoma patients, but I am not sure how/if they can reduce the pressure associated with tumor growth.
Regarding the fact that you live in Michigan, this link may be helpful; https://norml.org/legal/item/michigan-medical-marijuana