You are correct, it could have either of those meanings. Let's go with a less violent alternative.
You don't ever microwave fish at work.
1 Simple statement that, unlike Sue, who stinks up the office with her reheated trout, you have some decency and do not cook stinky food in an shared setting. You would likely only use this to contrast with someone who did do the thing you're commenting on.
2a Sharing a rule in the imperative sense. You're telling someone new to the office that they will not make friends if they make the place smell bad with their food. This is a calm sharing of social norms.
2b Still imperative, but with a serious mood change. When someone has violated an important norm, you might hear this as a serious admonishment or as part of an direct threat. The fish in the office example doesn't really fit here (for rational people anyway), so going back to something like your example, suppose your friend/daughter/whatever was assaulted by her partner. "You don't ever touch her again," would fit well, and "or else I'll do X" is either stated or implied.
It's not identical phrasing, but a particular line from the movie "Dodgeball" (of all things) kept coming to mind as I wrote this. To set the scene in this absurd comedy: Kate is at home and has a repulsive suitor show up. Another suitor/friend comes a bit later, tries to help her, but finds out that she doesn't need the assistance. Her line is, "You don't get to touch me, ever."
Dodgeball: A True Underdog Story