The Mirror They Refuse
There is a particular kind of person who, when something goes wrong, always has a culprit ready, and the culprit is always someone else. The pattern is so consistent that you eventually stop hearing it as a series of unrelated grievances and start hearing it as a single ongoing operation. The operation is this: a thing happened, the thing belongs to them, and they cannot afford to know that. So they hand it to you.
Projection is not a lie they are telling about you. It is the truth about themselves they cannot survive holding.
The strange part is that they often believe it. From the outside, it looks like dishonesty. From the inside, it almost never feels that way. The whole point of the move is to make the original memory unfindable. By the time the story has been retold, the wrong is yours, the harm is theirs, and the version they remember is the one they can keep living inside of.
Why it is cheaper than honesty
Accepting that you did something wrong costs something specific. It costs the picture of yourself as the kind of person who would not have done that. For some people that picture is load bearing. Removing it would bring down the whole structure. So the structure protects itself, automatically, the same way an immune system does, by identifying the foreign object and pushing it out.
The "foreign object" is the memory of the wrong. The "out" is you.
How to recognize it
There are tells. The story shifts whenever new information arrives, but always in a direction that keeps them clean. The same incident has a different villain depending on who is listening. Their account of their own life has almost no episodes in which they were the one who needed to apologize. When you challenge a detail, the response is not a correction, it is an escalation, because the detail is not a detail, it is a load bearing wall.
Why arguing rarely works
You cannot reason someone out of a position whose job is to keep a particular memory from forming. The position is not held by their reasoning. It is held by the part of them that decides what is allowed to be true. Bringing better evidence does not address that part. It just gives the projection a new target.
What you can actually do
Stop trying to give them the memory. They will not take it. What you can do is refuse to carry it for them. You can say, calmly and without theater, "that one is yours," and then not negotiate. You will not change their account. You will change which account you are living inside of. That is the only part of this you ever had the power to fix.
The point
People who cannot acknowledge what they have done are not strong. They are running an expensive, full time operation to keep a particular memory from existing. The cost of that operation is paid by everyone around them. Naming the operation does not end it. But it does free you from being the place the unwanted memories get stored.