Do people think you're just being lazy?

My husband is understanding until I can't do certain chores or have to rest. Then his whole attitude changes and I'm lazy or not contributing enough. There's almost a jealously of my condition--he gets mad that I have to "lie down" or "can't rake the leaves" anymore. I'm at stage 3. I see a pulmonologist regularly, I take all my meds, I go to physical therapy 3 times a week, I do everything I can, but I live in a two story house with a basement, stairs kill me. Even taking a shower exhausts me. When I sit still I'm fine though--you can't tell there's a problem unless I'm panting at the top of the stairs or walking like a snail if I go more than half a block. I'm only 52 and rarely ever smoked so it's hard to convince people there's a problem. Even if I show him my numbers and the literature, even when I can't talk because I'm so out of breath I'm dismissed as being lazy. He and his family have no idea how scary it is to not have enough air, how embarrassing it is to gasp like a fish in public. I look fine, I'm not frail. It's extremely stressful to not be believed because you "look fine." Those COPD commercials don't help either--I get "Look at those people, they are way older than you, on the same medicine and they're playing golf, running on the beach..."