Life expectancy of mother in law with COPD?

This is a difficult question to estimate life expectancy for someone. COPD is usually slow, however your MIL isn't a smoker, so how she got such COPD and emphysema you don't say. I imagine your family knows and you do not have to share that information. I'm sure the cause has been removed from her environment. In my experience, these two diseases progress slowly. This is not necessarily always the case, but this is only my experience. Best of luck to you and your family.