When people give you different reasons for doing the same thing, it doesn't mean they're lying. It just means that they don't know their own mind. (Most people don't.)

Humans rarely do anything or believe anything for the reasons they think. Those are just explanations the brain gives them to rationalize their behavior.

Motivations are more often than not explanations. Forming motivations is a top-down process. To find out why you really do what you do, you have to go deeper.

If more people understood this, there would be a lot less suffering and a lot less conflict.