Noun
wedge - A piece of material with a thick end that tapers to a thin edge, used to split, support, or secure things; also something that forces separation or division between people or groups.

The disagreement drove a wedge between the two longtime friends, and they really didn't enjoy spending time together anymore.
fairytale - A children's story about magical and imaginary beings and lands; or something that is too good to be true or seems unreal.

He told a fairytale about how he got the job, but no one believed him, and people suspected that he had a relative in management.