You're right Madgran emotional abuse is in many cases the reason why estrangement happens. It can be as you say, that children have been emotionally abused by their parents and it can be that an AC becomes involved with an emotionally abusive partner.
The latter is our experience sadly.
I do think it's important to be aware of who reads and posts on this thread in particular Onwardandupward. I am not disagreeing that someone raised by a narcissist may be 'attracted' to a narcissist in adult life, just as people who were physically and witnessed physical abuse during childhood, can be 'attracted' to someone similar.
That said, there are EP's here myself included, whose once close and loving relationship with their child has been torn apart and destroyed because of their narcissistic partner.
I apologise if I am being oversensitive to your post but fairly recently, there was an ongoing problem which was very upsetting for EP's being made to feel that the only reason their EAC was with a narcissist, was because they themselves were narcissistic.
I was actually on several occasions called a narcissist by a couple of posters who thankfully are no longer on GN. I appreciate that that horrible experience has no doubt made me very sensitive and again I apologise if I have over reacted.