Rejecting advice goes hand-in-hand with being defensive. When your immediate response to anyone who questions why you’re doing something or acting a certain way is to come up with a laundry list of reasons, it’s time to take a good hard look at what’s actually going on.
In the same vein, being defensive and rationalizing are two sides of the same coin. Generally, we’re defensive in response to others and use rationalization with ourselves. Telling yourself it’s okay to cheat on your diet with peanut M&Ms because the nuts have protein is a perfect example. If you have to make excuses when no one’s around, that’s self-deception.