Nothing and no one can get into your muscle fibres and make them tight and tense
Nothing and no one can change the action of your vocal chords to make you speak in an angry or anxious tone of voice
Nothing and no one can get inside your endocrine system and set off the cascade of stress hormones
It all changes when you change the way you process your perceptions, and it is the way you currently process them that sets off emotional reactions.
Learning how to examine your mental processing leads to resilience in the first place, and to quicker outcomes for meditation.
First of all, you become more reasonable and resilient in daily life, and the mind-self moves more easily through life. It is not budged from feeling that it is the whole of who you are, though. For that, you would have to sit with a still mind for regular periods, until you can see your mind. as objectively as you can see your hand. That is, regular still-mind meditation.
Secondly, if you do also practise meditation, reality-based thinking has already done some of the work. Then it is a matter of seeing that the mind is simply a part of human functioning, and not a special someone at all. That is the ultimate route to no stress!! And to no defensiveness, and no manipulations, and no aggression, and to being ok with reality as it is!!