Yeah at that point you are almost obligated to confront the person who was trying to avoid conflict. Like, dude, just say something. Assuming the worst is a very bad habit and very antisocial.
People know their neighbors. Consider that the neighbor might have been known to be anti-social instead (e.g. had one of the subtypes of narcissism) and resolving the issue directly was more likely to lead to a satisfactory outcome for both sides than confronting them because they were likely to escalate / not let go.
Assuming the worst at first is a bad habit but assuming bad intent after a bad track record is established is healthy and helpful.
Assuming the worst at first is a bad habit but assuming bad intent after a bad track record is established is healthy and helpful.