Nothing nice to say? Leave.

Some of you may think to; 

-> mock

-> quarrel 

-> criticize 

finds it your joke-of-the-day and make fun of the other party. 

But then again, please take note that you're actually in a way, testing one's patient limits too and at the end of the day, one might burst out and tears falling down. Why? Because, one is upset that they cannot be patient enough and that gave the answer that they think they're useless or hopeless. Why would someone do that? So, I guess if you have nothing nice to say to someone, you might as well just keep it to yourself. You don't know what others have been through. Well, unless if it's an opinion, then that is a different story. 
Alhamdulillah, for they are keeping strong in believing Allah and ready to face people like you. If not, they would make a choice to commit suicide. Who knows?