Two people can stand in the same place and leave with completely different realities.

Two people in the same room take away different accounts, because each one was filtering through their own concerns, history, and expectations. Neither is lying. This is worth remembering before you conclude that someone is being difficult about what happened.

In a disagreement about events, ask what the other person noticed rather than insisting on your version. You will usually find they saw something real that you missed. The combined account is closer to what occurred.