If the cancer is everywhere, I would start talking fast with your mother, maybe go visit her soon. My husband's mother called him to tell him she was that ill (and to ask him to tell his siblings for her) and was hospitalized and dead in less than a week. The speed was the startling thing.

My mother died when I was 3 but I learned a lot from my husband talking on the phone with his dying mother that one time. They remembered the good times and talked about what he was doing now and me (she and I did not get a chance to meet but she told him during the phone call, almost first thing, that she wished I had answered the phone so she could have spoken to me) and his future, etc.

I don't think there is any secret way to cope. It's going to be hard and painful; I'm so sorry Scotty. By the way, my always "present" wonderful, coping husband forgot his bank PIN number the day his mother died; came up blank, and he'd had the same PIN for 10+ years.