Is it normal that i can't eat or drink after anyone?

Sharing food is a wonderful experience. You are really missing out.

I don't like sharing drinks, because of the backwashing ect but sharing food I'm fine with it

You said that "If anyone even touches my food in any way I won't be able to eat it" .Do you like make all your own food? If so, you're missing out on some good mcmuffins

I don't mind giving someone a bite...until I see a bridge of spit attached to my brownie or sandwich

sounds like OCD

No, you have issues.