In this context ongoing means having repeated incidents of similar actions or behaviours.

Graffiti is visual, and if i have to see it every day that most definitely counts as 'repeated incidents' because it makes me feel like shit every time i see it.

Graffiti doesn't fit the definition of emotional abuse and equating with abuse belittles the effect of true emotional abuse

Once again i have to understate the word 'severity', because psychological abuse doesn't come in just one type or strength, some types are obviously more serious than others. That graffiti is illegal just about everywhere begs the question, why have societies decided that it is unpleasant enough to be a crime? What does it do to people? the answer is obvious, it is emotionally distressing.