Narcissists have no boundaries and see you as an extension of themselves, requiring that you’re on call to meet their needs – regardless of whether you’re ill or in pain. You might get caught-up in trying to please them. This is like trying to fill a bottomless pit. Their needs, whether for admiration, service, love, or purchases, are endless. You might go out of your way to fill their request only to have your efforts devalued because you didn’t read their mind. They expect you to know without having to ask. You end up in a double-blind – damned if you displease them and damned when you do. Narcissists don’t like to hear “No.” Setting boundaries threatens them. They’ll manipulate to get their way make sure you feel guilty if you’re bold enough to risk turning them down. You become afraid that if you don’t please them, you risk an onslaught of blame and punishment, love being withheld, and a rupture in the relationship. All too possible, because the narcissist’s relationship is with him or herself. You just have to fit in. Nevertheless, you stay in the relationship, because periodically the charm, excitement, and loving gestures that first enchanted you return.
Source: Do You Love a Narcissist?