Aw, I completely understand where you're coming from! I've suffered from germaphobia/emetophobia and it's one of the most terrible things ever. Especially in the winter months, I'm really horrified of touching anything
in our house besides the stuff in my bedroom. It was at its worst 2 years ago, but I still can't touch doorknobs without feeling dirty and disgusting and, as lame as it sounds, crying hysterically.
At one point I was using massive amounts of hand sanitizer and bleach on my hands to get rid of the "germs," but of course that caused my hands to become dry and cracked which was super painful. I know this isn't a solution, but they make sanitizing hand lotion
you might be interested in if the overuse of sand sanitizer/just plain old cleaning is becoming an issue.
As for recovery in the long term, though....I'm going to have to agree with what the person above said about exposure therapy. It's really difficult to ward away the evil thoughts that things are dirty and could make you sick, but it's totally worth it. I would suggest making your first step not washing your hands before putting a stick of gum in your mouth, preferably in public. Then move it up to placing a small piece of food on a counter top that people touch often and eating it. When you see that there's no ill effects from doing this, you'll become more confident in yourself and you'll be able to become less and less tied down by your fear of germs.