My husband has copd, when he's talking he gradually gets where he can't talk above a whisper.?

He gets an infection about every 30 days or so.I usually have to call the VA to let them know he needs some antibiotics. When he talks he get where his voice just runs out then he has to go and do a breathing treatment . He wheezes a lot especially at night. It worries me because I'm scared he might be close to the last stage. I don't know. When he feels better he likes to take the dogs out walking.