I'm making my afforts to stop now, but itseems to me that it's reaching everywhere now...how can I know what food has even the slightest amount of diery?
I'm not sure where you live, that can make a big difference. In the US packaged foods are required to list their ingredients and that will tell you. Anything containing the words "milk", "butter", (usually) "cream", "cheese", "whey" and "casein" are dairy products (usually derived from cow's milk). Especially look out for those last two, because they are less obvious and people might not know that they are dairy products. I know for a fact that there are products that say they are "non-dairy" on the front of the package and they contained theses ingredients, which is a lie. Often on the bottom of the ingredients it will list in bold items for people with allergy concerns and it will list "milk" on there if it contains dairy. that's a nice way to check without having to read through the whole list, but not every product has that and it will only say that for milk derivatives, not eggs. so you are best off just checking the ingredient list.
You can also call or write to a company and ask them, but I know that they sometimes lie and say that their products don't contain dairy when they do, because they knew that when people are asking that is what they want to hear and they won't buy the product if they find out that it does.
at a restaurant you can ask the service about the ingredients in the food and they will usually be honest with you or tell you if they don't know. In that case you'll have to use your best judgment. Most places have at least one vegan dish, it's usually french fries. But I've been to places that have had none, but only like one or two. Also be sure to ask about dishes containing lard and chicken stock, since sometimes things that appear to be meat-free will still contain these animal products.
Really your best bet is to talk to other people with the same diet, because they will know about certain things, because they go through the same thing.