I am so sorry to hear about your sister, but don't give up. Remain strong. There have been people with Stage 4 NHL that have survived 15+ years.
The chemo drugs are so effective these days. I am in remission from Stage 3 NHL. Dx 05-01-08. I was 41 at dx. I have seen patients at onc that were near death's door. 3 months later, they look wonderful. It truly is amazing how advanced cancer treatments are now.
Please take care of your sister and yourself. I will keep both of you in my thoughts and prayers. God bless!
Pam