When mistakes are made, we get defensive because of our ego. Ego prevents us from learning.
Nobody likes making mistakes but why not make a resolution to learn from your mistakes.
Even if 99% of it is another person's mistake, don't think of that. First, be honest with yourself and see what you can learn, then you'll be free from ego. Gain wisdom and accelerate your self-improvement.
Remember, mistakes are valuable as long as we learn from them.