Depression in full swing

So last night I found out that my mom has pancreatic cancer of the liver. This will be her fifth time having cancer. I think I might be in denial or something because I can't cry about, but I want to, it's just the tears will not come. I was told that she has 1-3 years left to live, they will be doing some aggressive chemo, but all I can think about is the worst case scenario and I don't know how to deal with it. If my mom dies, I don't know what I will do.