In English, the verb to touch is transitive and requires an object I am not touching it, at the very least. But maybe this phrase makes sense in Hebrew - but it just isn't being translated into English well? We would say her story is touching - to say it touches the heart, but otherwise, in English we would want to know what a person is touching. I would love to know more about this phrase and what the further implications are.
"Listening" needs something or someone to listen to or as in your case not to listen to. By saying "I'm not listening" you imply "Not listening to you, your chitchat or whatever". It requires the context to get the whole picture.
It is the same with "to touch". "I am not touching" and "I do not touch" they both cannot stand alone because they do not answer "what or which?" by themselves. As opposed to i.e. "I am not swimming". Think about the above examples you always need an extra information or the context to understand. At least in English. Maybe this is different to "אני לא ניגע". But since all translations I found for לנגע are transitive verbs I do not think so.