"Nothing other people do it because of you. It is because of themselves. All people live in their own dream, in their own mind; they are in a completely different world from the one we live." - Don Miguel Ruiz
Put Yourself In Their Shoes
The secret to growing a thick skin has nothing to do with developing a protective armour. The real secret to not taking things personally, is to grow our empathy muscle. They say "hurt people, hurt people" and thinking back to what we were feeling the last time we hurt someone can help us make sense of why we behaved that way and make a similar hypothesis about why someone else behaved badly towards us. From cutting someone off in traffic on the rush to work and in fear of upsetting our boss, to being cold in a social situation because we fought with our partner. Whatever it is, next time someone is unkind, it helps to acknowledge that there's a story behind it. With practice, we may start to feel empathy towards the people that hurt us, which helps to diffuse feelings of animosity and connect better with each other.
Realise That They're Filtering Everything Through a Single Perspective
I'm going to make a bold statement (with absolutely no scientific backup), and say that ninety percent of what people say to us is almost always about them. People's perspective of the world is filtered by their perception. Taking something personally is choosing to embody a single person's perspective, in the grand scheme of endless perspectives that are available. Everyone has their own set of standards, emotional triggers and things that make them impressed or unimpressed, so statistically, we can't be responsible for what other people think and there's not much point in trying to control it or letting it get to us. Trust that if someone has negative perception of you, it's to protect you from a relationship you don't need, or because it's time to move in a better direction.
Don't Be Guided By Their Opinion, Be Guided By Yours
While feedback is a wonderful way to accelerate growth, we ultimately get to decide whether someone's opinion resonates with us or not. When we're worried about the opinions of others, we're worrying about something that's out of our control and letting it control us. When the only opinion we take stock of, is the one we have of ourselves, we begin to hold ourselves accountable for being our best person we can be. Cognitive Dissonance describes the uncomfortable state when deep down, the wiser, more intuitive part of yourself knows that you're procrastinating from doing something that will help you grow. The only opinion we need to worry about is the opinion of our intuitive self, because that's the opinion that will lead us to our ultimate truth. If we listen to others and try to make everyone happy, we'll end up living completely out of alignment with ourselves.