I believe that.
Having worked in public relations, I have excuses and justifications down to an art form and it's quite possible that I have used both in most of the important areas of my life. But that's okay. It's a rough world, and we have to watch out for us. Sometimes we have to be our own publicists and we should always do what we must to make ourselves look good (justification).
The problem with excuses is when we start making them for someone else and it's not part of our job, and we make them to justify THEIR actions to OURSELVES.
Ex. *situation* You are in an abusive relationship. Let's say verbal abuse for the sake of argument. He yells and screams and calls you names.
You say: He had a hard day at work. He didn't really mean it.
I've done it (not in that kind of situation). We've all done it. What I ask myself is, how does it get to that? Why? I can't explain what drives certain emotions but I wonder what is it that it takes for one to become so certain of someone that you would be willing to make up excuses for them to yourself. That you would lie to yourself pretty much to the point that you are just blinded and have built in your mind a reality that's not real.
That's so sad.
First step: Admit that there is a problem.