Leonard, as writers it is our job to inform and help others if possible. If that means sharing our personal stories and exposing our vulnerabilities well so be it. I am sorry you received such a comment. We don't share such personal stories to receive a lecture from someone who doesn't know us or the full circumstances.
I agree with your statement, "If you can't say something nice and constructive...keep your mouth shut!" I have always tried to live by that. I haven't received any negative comments on Medium yet, but I am sure it will come.