Meet Tom and Ava. Tom is a raging narcissist who is married to Ava. Fortunately, Ava has figured this out and has been attempting to stop falling for the gaslighting tricks that make her feel crazy.
She's been employing the gray rock method and he's been really hating it. He is always trying to figure out ways to keep her feeling insecure and uncomfortable in their relationship.
For example, he knows it bothers her when he makes it clear he's attracted to other women, so one night after he particularly fails to make her feel crazy all day, Tom takes his manipulation up a notch.
He tells a story about a hot girl he met at the gas station on his way home. He tells Ava how the girl practically got naked in front of him (all lies, of course) and goes into what he would've done had he been single.
Ava realizes what he's trying to do, and she remains quiet to avoid his inevitable claims that she's always finding something to complain about, and that she should just blindly trust that he'd never do anything to hurt her (despite the fact that he verbally abuses her daily).
This is where it gets scary.
When Tom notices that Ava isn't giving him the narcissistic supply that he seeks, he takes it up a notch, claiming that he can sense that Ava is upset, even though she showed no signs of it.
Eventually, he manages to draw her into the argument and she is left reeling. She can't believe that he's done it again.
But this is how a narcissist works. He consistently and systematically tears down his victims, forcing them into these predefined roles (he defines them, of course) that place him in a position of power while she struggles to prove herself to him in some way.