Oh, Bozack...
I too know the terrible yuckiness that is public transit, but I ride the bus, and almost daily. My anger level is never higher than when I'm crushed on a bus with someone whose shouting to somone on their cell phone about "that bitch."
I've developed two personal rules that help me get through it. As a public service to you and anyone else here who uses public transportation, I'll list them here and encourage anyone else to post their own suggestions too.
Rule #1: always wear headphones, even if you are not listening to music. (this discourages crazy people from talking to you, or if they do, it allows you to ignore them without feeling totally like an ass. Also, if you aren't listening to anything, you can intentionally experiement with pushing other peoples limits in subtle ways like leaning into them and you can then hear things about yourself from the comments of those who don't think you can hear them.
Rule #2: Always carry a small sample vial of perfume or cologne, or an apple and/or orange. If you are stuck beside someone with body odour, mouth odour, bladder issues, etc. it is always good to have something that you deem "clean smelling" to keep near your nose to counter the effects.