Hello Gerri... I am sorry you are suffering so. My mother has end-stage COPD too, so I understand how tough it is to watch someone you love and who gave you so much in life begin to go downhill.
Unfortunately, I am not really able to answer your questions with the exact answers you are seeking. No one can really predict with absolute accuracy how long someone will live. So much depends on human will and other intangible, difficult to measure factors. Not to mention that in many ways the body is still quite mysterious even to medical experts.
My mom has been functioning at very low lung capacity for a whole year now. This time last year, I would not have thought she'd make it through the summer... yet here she is. Breathing is a bit more difficult each day and her world continues to shrink as doing EVERYthing becomes more and more of an effort, but yet... she goes on. At this point, I don't know how to predict how long my mom will be with us. Especially as she did quit smoking and uses her oxygen 24/7.
I can tell you that your mom is shortening her lifespan by continuing to smoke. That will continue to damage her lungs. Supplemental oxygen can be extremely helpful both in adding comfort and quality to life, as well as in preventing further deterioration of the respiratory system and overall health. If your mom feels that there is no point in stopping now that she knows she is terminal, it's understandable. But the quality of the life she does have left to her could be greatly improved by her quitting smoking and using her oxygen. And that is a gift she can give to those who care for her.
The bruising is probably due to her overall poor health, as is the weight loss. She may also be unsteady on her feet because she's not getting enough oxygen throughout her body and may be knocking into the walls or furniture and injuring herself, thus the bruises.
You can educate yourself about COPD/emphysema by reading through the many posts both Jane Martin and I have published throughout this site. We've written about all sorts of topics, and I have a whole series aimed at caregivers like you and me.
You might also want to ask your mom if you could accompany her to her next doctor's visit, so that you can talk with her doctor about your concerns and voice any questions you might have. But don't expect the doctor to give you an exact life expectancy either. The one year is probably the best you're going to get, and even that is no real prediction you can count on.
My heart out goes out to you... hang in there and do what you can to convince your mother that her quality of life matters. That, and just keep showing her how much she means to you.
Happy New Year,