Part of the head-wreckingness of being the Daughter of a Narcissistic Mother is that these women are quite often nice to us. It's not unremittingly awful.
They can be nice to us as manipulation if they want something. In this case it's a control thing, with an agenda - there are often big strings attached.
Or, they can be nice if they're getting all the admiration and attention and stroking that they need for their narcissistic supply. If a tiger is well fed, there's no need for her to pounce.
And so you may well have memories of lovely times with your mother, times of laughter and lunches out and shopping trips and so on.
This can be very confusing. Is she abusive or isn't she?
And of course, if you try to tell them you don't like the way they treat you, they can validly point to these nice times.
The thing is that there's always an underlying tension. You're only ever one wrong word away from it all going wrong. You can never relax. If you don't give her her due respect or adoration, or if you disagree with her, or whatever tiny trigger sets her off, then you get at best a cooling-off, and at worst, a bout of Narcissistic Rage.
You need to play by the rules, and then all is well.
Just never, ever EVER protest any treatment you get. The nice things are a favour doled out to you by her grace and favour. You actually have no rights. And if you try to assert rights - well, the fun is over and you're put back in your box.