Gas lighting takes away a persons ability to trust in reality and they can end up blaming themselves for the appalling behaviour of another person.
“If I was better/smarter/slimmer/kinder/quieter/cleverer/etc then they wouldn’t be so upset and frustrated with me”.
Other people can get pulled into it as well and can see the victim in the way the perpetrators wants them to so they miss the abuse that is happening.
This isn’t limited to gender roles either, despite the most common examples being reported as men abusing women. It also isn’t limited to partners; its a form of abuse that can occur with any type of relationship. Family, friends, work. I have worked with sibling abuse in this form and also adults who were raised by parents who did this.
It takes the victim time and space to trust their own perceptions again; to stop self blaming. They may never heal completely, but it is possible to bring about a lot of change.