Hi Powellypup,
Your world has been turned upside down as you say and while there's always hope and who knows what the future may hold, I suppose looking at things realistically, your mum may pass away soon.
You may find it valuable in helping prepare you and your family for this eventuality, by reading the following article - it addresses the issue "Many lung cancer patients and their loved ones want to know what to expect when dying of lung cancer". It's a sensitive but frank discussion, and if you visit the article, I would suggest reading a little bit, and if you think you may find the discussion distressing, then give it a miss or ask a friend to read it.
http://dying.about.com/od/thedyingprocess/f/dying_of_lung_cancer.htm
My other suggestion is for you and your family to prepare for the eventuality of your mother passing sooner than you expect, so you can do some thinking in the near future about both practical aspects and whether there are things to say or to talk about with your mum while there is opportunity to do so.
I stress that I'm not medically trained so I'm offering my personal opinions here. I hope your mum can stay in this world with your dad and you and family for many many months to come.
Ed.
