Adam Newbold blogged last month about resisting the urge to respond to some posts online:
The urge to engage can be overwhelming. It’s normal to want to respond—to correct a mistruth, to set the record straight, to defend a point, or to just add words of strength and courage in the proximity of hate and negativity. But it’s really best that you don’t.
It’s difficult sometimes to know when it’s appropriate to reply and when it’ll just make things worse. One way to think about it: is my comment going to be welcomed and considered by the recipient, even if they disagree? If not, skip it.