Humans can form opinions as fast as 50 milliseconds.
A recent tip I came across to staying neutral when facing negative emotions: Look at your whole, naked body in the mirror every day for five minutes. Stay focused. Stay neutral.
»The only man I know who behaves sensibly is my tailor; he takes my measurements anew each time he sees me. The rest go on with their old measurements and expect me to fit them.«
George Bernard Shaw