Scared of future need answers

My COPD is getting worse I want to know "What Next" "Long will I Live" .. I have a great respiratory nurse but she won't answer any direct questions. My next step is oxygen and I have heard so many bad things about this. That the lungs get weak and rely on the oxygen doing the work. I have witnessed a COPD death and I don't want to die like that it took 45 minutes to die.