One of the problems with having instant, immediate access to others is human nature itself. When something upsetting happens, it's natural to want to be in contact with your friends. When someone tweets those instant intense feelings, there's no taking it back. Tweet or text, the instant comment can seem absurd even to the sender after a few minutes.
Before sending that message, take a few deep breaths, engage your brain and think. It's far easier to think a rant than to suffer the consequences of sending it.