Don't marry your beliefs
If you ever find yourself saying, “there were mistakes made, but not by me,” then you might want to consider the possibility that you're going through cognitive dissonance. That you are holding on to a belief you aren't ready to give up, not just yet.
It's hard to tell when you're being cognitively dissonant, but if you can see yourself rationalizing a belief when faced with contrary evidence, that's usually a good time to try and re-think your belief (and your assumptions that led you to having that belief in the first place).
If you must believe in something, believe in the falsifiability of it first, and then wear it loosely; don't marry your beliefs. Don't believe in them so much that you will need them to be true no matter what.