Air: A Necessary Evil

Okay, let's talk about air.
I know it's necessary for survival, but have you ever wished that oxygen was not a critical element of our existence?
I've always had trouble with places where people are (and have you noticed that people tend to be in an awful lot of places?), not only because of the risk of someone touching me, but because I have to breathe the same air as everybody else. It's somewhat easier when I'm outside, since there's actually somewhere for the air to go, but in enclosed places the thought of sharing air makes me very edgy; and the smaller the space, the worse my anxiety.
I was watching an episode of the Obsessive Compulsive Detective the other day (I love that show: it's so refreshing to see somebody else acting like me!) and there was this scene where Adrian Monk (the detective with OCD) is in a doctor's office and starts holding his breath, because he's afraid of catching some disease. I started cracking up, not because it's really that funny, but because I actually do that. It's not so much that I'm afraid of getting sick, as that the thought of breathing in that particular air is absolutely revolting. So I'll breathe in through my nose (I have this idea that inhaling through your nose will admit less germs, dust, dirt, and general grossness than inhaling through your mouth; no idea if that's true, but that's the principle I operate off of), hold my breath for as long as I can, and then exhale. The thing is, I have this other idea that if I move my lips too much, or open my mouth at all, the germs will get in my mouth and I have to blow them out. So then I'm inhaling through my nose, holding my breath, and blowing out through my mouth, while trying to keep my mouth mostly closed so that nothing gets in. I have gotten the weirdest looks for doing that.
I thought I was doing it inconspicuously, until I got a few of those 'and-what-planetary-system-are-you-from' looks. Then I did it by myself in front of a mirror. Yeah, not that inconspicuous. Not that it matters. I keep doing it anyway.
Apparently most of the air we breathe is produced by little algae things in the ocean, so I'm thinking of buying a houseboat and living life on the waves, so I can get the freshest air in existence. Only problem is, I'm scared of water, too. Hmmm. Scared of air, dirt, and water. What planetary system am I from?