WE ARE all artist in our mind, I think. But we also have our opinions and perhaps because we are artists, we have strong opinions about some imagery.
Also.... as much as we don't know about you and you as a person, you don't know about the person who posted harsh comments. You have no idea what hurts some people or evoke an emotional response. I saw your image. I don't see anything really wrong with it. But perhaps someone had a close friend or family member affected by the problem, or maybe himself/herself is.... and thought you were exploiting it. Emotional response may be the reaction. I don't think we can blame that person.
One thing is true.... you evoked strong reaction/emotion. It just wasn't the kind you wanted.