I'm going to highlight what I believe to be a mature and higher understanding of this dynamic and that the common belief of it all is entirely seeing it wrongly. Opposites attract and you're supposed to work together and meet in the middle. That is why such attraction even exists in nature!
To be fair, I will mention my stance is mostly from an empath's perspective. And we empaths just as much as narcissists have this strong notion that we are right.
Empaths have a strong notion that they know how the world should be. Narcissists have a strong sense of realism backed by their confirmation bias or life lessons.
For empaths to strongly cast out someone because they are too toxic is indeed an empath walking away from their calling. They are "too hard" to fix. Essentially, the empath is refusing to self-reflect enough and see their own flaws because being around a narcissist highlights them. Narcissists only see that as furthering their own views and feelings of the world that everyone is selfish so why not give in and enjoy the ride? Even an "Empath" gave up on them. They know they are being intense, purposely. They want to see how you react in return. Part of them secretly wants you to show them you are light and love. Their higher selves. They want to be saved but their need of control because they are afraid of being seen truthfully, shakes them up. Their strong egos full of cravings is a defense mechanism.
BOTH have to meet in the middle. Empaths stay stubbornly strong about your unconditional love without becoming as self-important as a narcissist. Essentially wearing what you "hate". You become "light warriors" and instead seek out soulmates or clones of yourselves as being true love. Closing off some of your empathy in it's wake. Narcissists, grow up and see that you are adding to the cycle rather than fixing it because you "deem" it hopeless. Have mutual control. Be mature!
Be the change you want in others! BOTH of you. EVERYONE has growing to do and being stuck on your stance, self-importance invites ignorance.
The real reason you two are so drawn together and sparks fly easily is because you two are opposites. Opposite attract. You want a peak loving and strong foundational relationship? SEEK and WORK with your opposites. That's how the universe teaches us all. Strong feather rattling. Clashing.
Want the most 'perfect' and loving relationship? Strip your ego, spirit, mind, body, soul, etc. entirely bare! Hope the opposite does the same and you both mend each other. Become imperfectly perfect and as one. THAT is the peak of love between two people. EXPLOSIVE Love that needs not even give insecurities, worries, or anxieties an awareness when you're around each other. You compliment each others' flaws.
I am writing this because I hurt and grow tired of seeing these two ENABLE each other by wearing their victim stances or stubborn "realism". Hope these words help out at least one of you.
God bless, light and love, or whichever uplifts you to your best divinity and self-growth with positive abundance. I wish you the best!
Gracefully, I am open for debate and even my views to be turned upside down. Please, this is indeed open for discussion. However, I will be very blunt towards anyone who wants to indirectly condescend it with their own self-importance because that is proving to me you hardly absorbed these words and aren't "open" to this discussion, just looking to belittle it because it threatens your perception or ego.