Gaslighting in slides via Psych2Go.
The gaslighter gets the victim to doubt themselves and their memory and perception by telling persistant lies such as:

The abuser will blame you for several things, twisting arguments around to dump the fault on YOU. You are on a repeat round-trip ticket to ‘blame/ville’ on the guilt train.

You’re frequently let down by them. Gaslighters typically don’t keep their promises and their actions don’t match what they say. You’re constantly asking yourself, “will they follow through this time?”
They see no gain in consistently keeping their promises so- they don’t.

You question EVERYTHING.
Normally, curiosity is a good thing. Asking questions helps us learn. So of course, count on a gaslighter to ruin it. The horrific repeated insistence that ‘you’re crazy’ or ‘you’re making that up’ eventually breaks down anything previously stable.

Without that solid foundation you start to wonder if all the terrible things they say are true. Gaslighting can unfortunately have lasting damage. Awareness of key signs is the first step to protection from manipulation which can then lead into the healing process.