plenty of things are sad or joyous or stressful. that does not automatically mean you have to react in a 'predictable' way to these influences.
you are the boss of your own self. that includes your energy and your emotional reactions. it may seem as though someone can take these things or cause these things in another, but that is an illusion - one i would daresay is 'ego driven' in the one who thinks they're doing the controlling lol. a person has to allow themselves to be manipulated.
you may not realize you're giving permission, but you are by your knee jerk reaction to what goes on outside yourself, rather than taking a proactive approach to how you feel.
If you have not practiced with your subtle energy then it can easily be removed by someone who is wee versed in its manipulation.