I have read this thread from start to finish and have been following it closely.
I really only have one thing to contribute.
I took an anatomy class this year and took a picture of these lungs...
This is what lungs look like from second hand smoke, you can still see tar...Obviously second hand smoke has SOME effect.
Now these pictures aren't mine but this is what a healthy pair of lungs looks like...
And last of course this is what smokers lungs look like, this is from someone who smoked almost all of their life...
Now if you are someone who is alright with doing that to your body, your LUNGS, something is not right in your head.