Because all the noise about how the other party is better off triggers zero-sum thinking, often the benefits we receive fade into the background like they’re nothing. This feeling of defeat gets hold of us. Truthfully, we might have received fewer benefits from a certain situation, which is nothing to be proud of, neither does it make you a person with higher moral values. This might mean that you need to improve your negotiation skills and stand your ground next time. Being pushed around is not a desirable outcome, after all.
However, less benefit still does not mean it’s nothing. You don’t need to trick yourself into believing in either side. Seeing all this in a realistic light is ideal, indeed.