Don't believe everything you think, and absolutely don't believe everything other people think. What is true for someone else may or may not be true for you. There are vey few shared universal truths. And enjoying fulfilling personal relationships is NOT dependent on having an identical world view. What is true today may or may not be true tomorrow. The world is in a continuous state of flux. And if we use science as our guide, what we thought to be fact very often turns out to have never been true at all. (Check out the film "What the Bleep Do We Know" for some great eye opening examples of what we know and what we think we know.)
The relationship skill to acquire is to insert "maybe" into your internal dialogue. Maybe you know why that jerk did such and such. Maybe you know why your friend is so upset. Maybe you know what's best for everyone involved. Maybe you know why your coworker is being so contrary, and maybe you know what the only solution is to a current struggle you are dealing with.
Practice remaining open a little longer than is typically comfortable. Practice trying to see the opposite perspective from the one you hold. Don't jump to premature conclusions. Play the "What If I've Got It All Wrong?" game and practice active inquiry in your communications. Take a good long look at cause and effect.
As I left the dentist's office the other day, I remembered the value of "maybe." I'd had my teeth cleaned and the hygienist was lecturing me about the extreme deleterious affects of my slip shod attention to my nightly flossing. Maybe she is right. Maybe my gums were bleeding because I'm not a skilled flosser, or maybe they were bleeding because I have a sensitive mouth, and she was jabbing me with a very sharp instrument. Maybe the "infection" is going to travel through my blood stream and damage my liver and kidneys, or maybe it's the other way around. Maybe my mouth is sensitive because I worry and experience existential terror that causes my pericardium not to operate in its ideal fluttering manner which sends mixed signals to my liver and kidneys that stresses my digestive and endocrine systems releasing stress hormones into my body, affecting the sensitivity of my gums....I'm just sayin' "maybe."