When I was first diagnosed with bipolar disorder, my mom and my grandma attended NAMI Family-to-Family classes. It helped them navigate the uncertainty and the fear of my diagnosis with information from other family members.
From nami.org: "NAMI Family-to-Family is a free, 8-session educational program for family, significant others and friends of people with mental health conditions. It is a designated evidenced-based program. This means that research shows that the program significantly improves the coping and problem-solving abilities of the people closest to a person with a mental health condition.
NAMI Family-to-Family is taught by NAMI-trained family members who have been there, and includes presentations, discussions and interactive exercises."