8. Their stories contradict one another
When it comes to the truth, there is only one version and we all know it, although lies and other untrue things might be told in many ways.
Speaking of that, lying is often associated with forgetting all sorts of things, which is why a liar could come up with MANY versions of an answer to the same question. You might easily forget your lie, but the truth never changes.
Any time your partner’s story changes or somehow develops into something different than what they’ve previously told you, take it as a red flag that they’re hiding something from you.
However, there’s also the case that they’re so convinced of their lie that they believe it is indeed true, and in that case, their story will always be the same.