AITA for refusing to eat something my roommate touched?

My now ex roommate didn't shower in like three months and barely ever washes his hands, not even after using the bathroom. I don't eat anything that touched his bare hands, unless I know he washed them right beforehand. So when I start a bag of chips and he takes some out for himself, I give him the whole bag cause I don't want to eat from it anymore. He always calls me mean for it but I can't get myself to eat it, if I think about what kind of bacteria might still be stuck on his hands.