Dorothy,
I am so sorry to hear about your Mother--I know what a sad and painful time this is for you and your family.
I lost a very dear friend to liver cancer a few weeks ago. I was one of his primary caregivers. He was diagnosed five months ago with PLC. His condition was terminal and no treatment was offered. Despite this, he seemed to be doing so well. At times, it was difficult to believe he even had cancer. I don't think he believed it either.
But as the doctor said, once it begins progressing, it happens swiftly and and a frightening and alarming pace. The symptoms you described for your Mother happened to my friend. He went from being totally independent to bedridden, and very, very sick, in a lot of pain--all within a few days. He went to the hospital the final week, slept almost all the time, stopped eating and drinking and slipped into a coma the last two days before he died.
Your Mother most likley only has a matter of weeks or days left based on what you said about the condition of her liver. It sounds like liver failure and life cannot be sustained without the liver.
Spend as much time as you can with her and celebrate these final days of her life. Let her know that you are there--ensure she's free of pain--say everything now that you want her to know because any day she might slip away.
God Bless you and your family. This is such a hard journey that no one should have to go through. Thank God your Mother has you and your family to be with her during this time.
I will say a prayer for you and your family.