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Speaking form my own experiences, I can say that an air purifier will definitely help make breathing easier. Humidity is the question mark in this. Usually about 40% humidity is ideal for COPD sufferers. But each individual is different. I have an air purifier in my living room, and it definitely helps me breathe easier. Drier air is better for me, but more humid air might be better for your wife. That is something I cannot answer. Wish I could help more. God Bless!