This is great advice on taking responsibility for your own emotions. The approach you describe is mindfulness: observing what your emotions are, rather than jumping to a conclusion. This is very powerful indeed - even the couple of moments it takes to do this quick analysis can make you feel more in control. Mindfulness also teaches us to accept the emotion and not try to quash it. Whenever I hear "You shouldn't feel that way" I respond that I am simply communicating what I feel. We can't control our emotions, but we can control how we respond to them.